Engineers: Of course, run hot oil through the spaceframe itself! Simple, elegant, no downsides. Drivers: HELLO, THIS IS LITERALLY A TOASTER NOW, AND I'M THE BREAD
had a good chuckle when he explained that part. "why the hell would they discard it?" "oh." i honestly thought it was a genius space and weight saving. totally forgetting that someone's actually driving it.
Not sure why we are getting excited about the oil running through the chassis to the oil cooler. Pretty much every race car of that period did that. Only stopped happening when the sport moved to monocoque chassis'
RCR makes a continuation. Only issue is your engine options are limited unless you manage to have an original flat-12 lying around. Cobras, GT40s, and even Lola T70s have the advantage of numerous V8 options. Personally, I wouldn't want a 917 replica with a 911 engine or a V8 stuck in it.
Porsche got inspired by Lola T70 rear shape in order to create downforce in the rear axle, and it worked the car no longer swerving in the straights so much.
Per _Porsche 917_ (by Gordon Wingrove) [page 58], the bug-spatter discovery/downforce solution did not come from Porsche, but from John Wyer's engineers at JW Automotive (who Porsche employed to sort out 917 problems and to make improvements). Book excerpt [my inserted comments are in brackets]: _After some tyre testing, the Wyer personnel were invited to become involved_ [with the 917's aerodynamic issue]. _John Horsman_ [JW Automotive Engineering Manager] _was well-acquainted with high-speed aerodynamic problems, having been instrumental in using spoilers to stabilise the early design of the GT40. He spotted that while the front of the coupes were covered in dead flies and gnats, the rear spoilers appeared to be clean except for the very top edge -- which indicated that the airflow was mostly passing above them. After a group discussion between both the Porsche and JWA engineers and with some dimensional input by John Horsman, Cuoghi_ [JWA Chief Mechanic] _and Davies_ [JWA Mechanic] _then set about building a rear 'deck' for_ [chassis] _008._ [Note: The 'deck' was effectively the "boilerplate" for the rear-end fix that resulted in Porsche/JWA joint development of the 917 short-tail version, i.e., the 917K.] _Brain Redman went out to try a couple of laps in the_ [modified chassis 008] _car -- and stayed out for more as he gained confidence in the handling. When he came back to the pits he is quoted as saying 'now you can_ drive _the car..._
They should place fluids in the frame maybe not fuel though. Oil or maybe a very inert coolant. The level of engineering was insane. The text on the tyre heater 'remove before flight' a little foreboding! The cooling fan atop the engine like like a tyre rim. PS, yeah I got to that part now. Never crossed my mind about cabin heat. How was the frame filled with nitrogen and fluids? Or was the pressure monitor removed for the fluid frame?
The 917 wasn't the first racecar to use a pressurized tube frame. Don't remember who had it first. Maybe Lotus. Also they would pressurize the frame and put it in a swimming pool, looking for bubbles.
It's actually very difficult to save weight replacing steel with aluminium as aluminium does need more material to give similar strength conpared to steel. Only when going for Magnesium alloys the balance shifts in favour of the lightalloy . But the there is Titanium , just as delicate and elaborate to work on ..... The Kauhsen 917 LeMans winner was ,according to Willi K. himself one of the very few 917 chassis made from magnesium alloy tubing ....
I wonder if they could have fixed the problem of the air detaching from the car by adding small plastic vortex generators to the top of the car. Works wonders on airplane wings to keep the airflow from detaching!
Nitrogen doesn’t react with the metal due to displacing oxygen preventing corrosion also it’s a dry gas that does not react much to temperature causing a pressure rise or fall. That’s why we use it in HVAC
Here's an idea. Instead of pressurising the tubes, create a vacuum instead. Alerting to failure if air re-enters. This would also save a little more weight no?
Not ridiculous at all. The same basic system (except with compressed air) is used in many tubular structures that rely on weld integrity for their strength - crane and drag line booms, for a start.
Only thing I would like to add is km/h alongside with mph for us who aren't familiar with mph. Otherwise it's once more a great video, I love this kind of content about engineering and mechanics and you explain everything so well Scott! Thank you!
@@Driver61 if you are keen to receive feedback, i kinda wanted to close the video halfway because the way you edited your speech, you didnt leave ANY space at all, its like reading a sentence without commas or periods, it felt weird, also, this could be just be me, but the pace is also weird, it goes like this "but not every sentence NEEDS to have HIGHLIGHTED wordsFOLLOWED byfastwordsthatendin s l o w w o r d sONLY to not LEAVE any space BETWEEN senten c e s" Tl:dr: a small break here and there, in my opinion, would make it sound a lot more natural. Edit: i did enjoyed the video though, excelent investigation, presentation and footage (:
so it was a stone that flicked up into his visor from the lotus in front that ended his career? :O oh yeh he also set the fastest ever lap on the targa florio. record never broken.
5:35 "... they pressurized the entire space frame with nitrogen..." Having indication of cracks it's not the only and probably not the most important benefit of pressurizing the space frame. Pressurizing a space frame allows you to use thinner material yet still avoid buckling. think of how you could stand on a full can of Coke, but there's no way a depressurized can would support your weight. The Atlas missile also used this method to avoid buckling while saving weight. doesn't even take that much pressure. so well it may have provided a convenient indication of any cracks, the main benefit would have been the ability to use thinner gauge tubing.
@@noneofyourbusiness4294 In real life standing on a soda can and certainly in real life in the frame of a race car pressure is never applied evenly. In real life, thin world tubes are subject to buckling instabilities. To close approximation, thin wall tubes of the same external dimensions differing only in wall thickness will exhibit the same stiffness until the point the wall buckles. pressurizing the tubes isn't some afterthought or just a check for leaks, It is fundamental to the strength of the frame.
@@bengriffin4027 the nitrogen is still a gas though so it's compessible. even if it may help resist buckling a bit, the amount of gas displaced when a tube collapses only raises the gas pressure in the entire frame by a bit. Don't forget soda can's are filled for more than 90% with an incompressible liquid meaning a small change in internal vollume greatly compresses the tiny bit of gas at the top, proportionally speaking. The Atlas rocket was also filled with liquid propellants and when these propellants were drained from the tanks as the rocket went up, the weight of the rocket also decreased so the airframe was less stressed allowing the airframe to better support itself. Besides that, the propellant tanks had different length/diameter proportions compared to the 917 frame which allowed them to act more like a balloon. (same goes for the soda can)
@@ddewaard3265 Indeed. The compressibility you raise is a very good point, and even if that were not the hypothesis-killer it clearly is, the soda can analogy has another flaw: the relative wall thickness of a soda can (as a proportion of tube *diameter* ) is several orders of magnitude less than in a chassis tube of maybe 16 to 20 OD x 2.0 wall. To provide meaningful anti-buckling support in the latter case would require ridiculously high gas pressures, which would cause the elements which were right-sized for tension forces past their failure point. In any case, the valves for filling the tubing with gas (which is generally understood in the engineering community to have been air rather than nitrogen in the case of these cars) were nothing more than conventional Schraeder valves, hence completely unable to hold the very high pressures anti-buckling would require.
And it was quick, to the point, and something actually cool instead of some of the obnnoxious garbage most sponsors tend to be [*cough* bRiLlIaNt *cough*]
That reminds me of a joke. There's a car accident accident and someone shouts out "is there a doctor around here? It looks like the driver is going to die!" Someone says "I'm a doctor of philosophy- everybody dies!"
The "aerodynamic development by flies" did not happen at Le Mans. It happened at the Osterreichring old circuit during a test session. Porsche had contracted with John Wyer Automotive Engineering, who'd beat them twice at Le Mans with Ford GT40s. John Horsman was Wyer's race engineer, and he attended a test session in the summer of 1969 to get a look at his new charge. When he arrived, the Porsche team were chasing handling gremlins. They'd make an adjustment, swop parts, etc. then send test driver Willie Khausen to do a couple of laps. When he came in, they'd ask his impression, compare lap times, etc. Nothing worked; no matter what they did to fix the handling, the result was always, "no improvement," or "it's even worse." When the team took a lunch break, Horsman looked the test 917 over, carefully. That's when he discovered that the bug splats hitting the front of the car, as expected. But curiously, there were almost none, past the doors. He also spoke with other drivers testing other cars and discovered that they preferred the greater stability of the short-tailed cars to the nominally faster long-tailed, stream-lined ones. After testing ended for the day, Horsman asked the Porsche engineers if he could borrow some sheet aluminium and the team's second 917 chassis. That evening, he and his chief mechanic cut up the aluminium and duct taped it on the car, creating wedgy box that covered the rear wing to roughly the top of the cockpit height. Next morning, Khausen took the modified car out for a drive. The Porsche crew expected him to return to the pits after a couple of laps. Instead, he kept on going. When he finally did stop, the engineers asked why he didn't stop. Khausen looked up at them and declared, "Finally, this thing is a RACE CAR! Now we can work on it." Horsman's "box" was refined into the wedge-shaped tail the 917 was famous for, and the rest is history. And a Steve McQueen film. Ultimately, Porsche did get the long-tailed 917 to work by raising the rear wing and re-sculpting the tail to reduce lift, but it's John Horsman's on-the-spot improvisation that made the car a winner.
Interestingly, in a recent interview the other Porsche works driver present, Kurt Ahrens (also the winner of that 1969 Austrian grand prix with Jo Siffert), says it was basically him who came up with the idea, which would have to do with his family business, a metal-selling/scrapping company, in which he was constantly playing around with scrap as a kid, making his own cars. He was passing through the formula classes for Brabham, battling in Formula 2 often successfully with Clark, Hill, Rindt, Ickx... while being his own mechanic as a privateer (financed by his family business), and was known for having enormous mechanical empathy with the cars, the kind of guy who'd notice right away that the rear left wheel is slightly out of alignment or that the dampers were on their way out, and would have an idea how to fix it immediately; also he never crashed a single car during a race, known as a very rational and disciplined driver, so he was hired by Porsche to help with 917 development, a difficult job he was extremely well suited for. He suggested to the engineers to get some aluminium sheet from the hardware store in nearby Knittelfeld he had noticed on the way, and simply sticking it to the rear to see what that would do, the kind of thing he'd do to his own car; and it was applied that same day (perhaps after coming up with it independently after considering the fly-splatter-pattern, who knows); the brits ran with the story ever since. He's one of the more humble, shy and down-to-earth characters in racing, certainly not into fame and recognition - actually turning down driving F1 for Brabham after one race as he figured, this F1 circus with worldwide races wouldn't allow him to be with his family and the business anymore, and he's quite rare to give interviews. He says he asked Piech and Peter Falk soon after the 917 story if he should offer a correction to that story to the public, but it was suggested after a bit of quiet consideration for him to keep quiet, as that story would play better with the international audience if it were the british, making the 917 a more international project so to speak... I would say, that would be entirely in line with what is known about Piech and his strategic mind. David Piper who also partook in in that Austria 1969 race confirms that story. Oh, and the other guy's name is spelled Willi Kauhsen, if someone wants to look him up. If he had told that sort of story, I probably wouldn't believe a word, he's a great character and absolutely entertaining to listen to, but definitely a story-teller never shy to "emphasize" his own role in whatever happened. Ahrens is a very different character. In fact, it doesn't matter too much who actually came up with it first - they had a lot of brilliant and highly motivated minds pulling all-nighters and working their ass off to get this car right.
@@z33r0now3 Sure, the interview with Ahrens there is the longest that he has given (in public) to my knowledge, other than the interviews he did with his long-time friend Eckhard Schimpf for his book ("Einer dieser verwegenen Kerle") which is also a good source on his involvement in 917 development. At any rate, I find it hard to believe that the often-quoted fly-pattern actually tells so much useful information, at least not in the way it is most usually mentioned about the 917 (lots of flies in the front, no flies in the rear, ergo bad airflow on the rear) - I'd expect that the rear on any car, even several ones with very much working rear aerodynamics will be comparatively clean of flies and other debris as the impact of those particles will mostly happen around high-pressure spots such as the frontal area, not an area of laminar flow as you'd want along even an effective downforce-producing body section at the rear. With the early 917 tails that they ran, the only part where I'd expect any splatter would be the vertical stabilizer, perhaps that's what they meant. I'd hazard the guess that the decision to let this be claimed by the brits was also influenced by that fact that at Porsche there were several big heads (which may have included Piech himself) who held the "streamlining" concept in the highest regard - as is logical for a company used to bringing small-engine cars to Le Mans, one of the fastest races there was; their natural instinct in terms of aerodynamics would be to run as clean as humanly possible. I'm sure there was some hesitation to "ruin" the car in that regard with that rear spoiler section, which held back the performance initially - and even if the problem was known to several people including Ahrens, the situation may have required an external actor to pass..
@@decnet100 interesting comment. Food for thought. Thanks for replying. I drive the 917k in a simulator on the nordschleife in Virtual reality. It’s my fav race car besides 908/956/962. it’s not the real thing and it’s already so bonkers to hold the car on the track, makes you appreciate how hard it really must have been.
7:50 In the picture it's the 917K which has the correct aerodynamics. It was actually the prototype 917 with a sloped down tail that's unstable. That's why the later 917s have a raised bodywork towards the end and often some small deflectors to achieve more downforce. Apart from that you are explaining it brilliantly. Great respect to you! 👍
There are "some" (toooooo many) other Facts he did wrong. Mostly everything about the 1st longtails and that K just means kurzheck / shorttail and so on.
"Porsche 917 - Wikipedia" en.m.wikipedia.org/wiki/Porsche_917. In the 1973 Can-Am series, the turbocharged version Porsche 917/30 developed 1,100 bhp (820 kW).
Big thanks to Ridge for sending me this wallet and supporting the channel! Find a link in the description to get yourself 10% off! Weight saving level 100! Who would love to have a go in this iconic Porsche? Hope you're all glad I pronounced Porsche correctly this time! NOTE FROM EDITOR: We're very aware we show the 917K when talking about the 917, however there is very little good footage of the 917 out there. Given most people wouldn't be bothered by this detail, we used the 917K footage. But if you spotted it - 10 brownie points to you.
Great video, as always. I do have to get used to your Imperial System. Could you at least put the speeds in km/h as text on screen if you do not want to mention them please?
1 - The 917 has a 180 degree V12, not a flat(boxer) engine. In a V engine opposing pistons share a crank pin, in a boxer each piston has their own pin. 2 - Another neat thing about the 917's engine is that in the middle of the crankshaft there is a gear that connects to an intermediate shaft that drives the flywheel and ultimately the car. This essentially halves the flex the crankshaft has to withstand, which in a 1000-1200 bhp long V12 engine is quite a good idea.
@@Jacob-W-5570 I actually thought it was a neat idea as well when I saw an engine cutout at the Porsche museum in Stuttgart. Definetly worth a visit if your close by. Though the Mercedes museum in the same city is much, much better.
I am happy you mentioned that. It is my assertion that taking the drive at the minimum first degree node of flex allowed the use of smaller crank bearings resulting less internal drag on the crankshaft. I.e. less parasite engine drag allowing the power that would be lost to drag on the crank to be used to propel the car.
True on the center power take-off on the engine.....and here's another 917 tidbit......the mating gears have a "hunting" tooth.....one gear does not have the same number of teeth as the mating gear...so the "Same-two" gear teeth don't mesh with every revolution. So an interesting question emerges.....when you see the RPM of this engine, is it the crankshaft speed or the slightly different output shaft ( clutch) speed......oops .....time's up. Cheers !!!
As often as you see him in the RB paddock during the F1 races, you tend to forget Helmut Marko has had some incredible motorsport accomplishments of his own.
@@ProVision3187oh yeah? i just repeated the sentence that was written in the video and corrected it. other guy said there are differences between 180 deg v engines and boxers which is true , and the second guy said 917ks engine wasnt a boxer which is also true. so what the fuck are you even talking about
Ryan Miller wrong , flat means both boxer engines and 180 degree V engines. They are called 180 V because their arthitecture is same as a V engine. In a 180 V engine 2 pistons from opposite banks share a rod journal (crankpin) and move together. Where as in a boxer engine each piston gets its own rod journal and therefore isnt connected to the cylinder at the opposite bank and dont move together. In fact they move in opposite directions to each other.
Amazing video ( as ussual). Just one complain: Please try including logical meassuring ( aka metric system) Cause pretty much no one - but the US and a few other non-logical nations- uses Imperial anymore. Thank you
It should also be noted that this video is primarily focused on the original , coupe 917 used for endurance racing as for LeMans. Engines were 4.5 liters....later 4.9 liters...and finally at 5.0 liters. Horsepower went from 520 to close to 600. What is missed here, is that all this engineering and details, are also found in the previous racing models,where the 917 is the culmination of this evolution of the series. The 906, 907, and especially the immediate predecesor 908 , had the same frame design and nitrogen pressurization. Even the basic engine design of the 908 was "Somewhat" carried over, as 908 only had an 8 cylinder engine, at 3 liters size.....it was "basically" the same as to items like pistons and connecting rods ( 12/8 x 3 liters = 4.5 liters.....the original 917 engine size). The 908 had around 350 hp so the estimate of 520-525 for the original 917 engine translates reasonbly well, too.
porsche engineer: so how is ze car? very fast yes? is good? porsche driver: oh it's fast alright, it's actually scary at times but i'm sure all the safety features will keep me safe right? porshe engineer: ze what now? porsche driver: safety features? porsche engineer: ah yes *looks around nervously* we've made this of course porsche driver: i mean it gets so fast at times i feel like i would die instantly if i crashed haha just joking porsche engineer: *nervous laughter* haha yes well alive dead who are we to say, maybe it's all a simulation i mean am i alive right now? are you alive? what is life even you know porsche driver: ...what do you mean? porscheengineer: oh don't worry just being silly...driver who accepts the terms and conditions of the contract that clear the porsche engineering team of any liability in case off a fatal crash says what? porsche driver: what? porsche engineer: gotem, oh wow would you look at ze time i have to go now to work on these safety features that are totally real, don't forget to hug your wife before ze race yes? for good luck...bye now porsche driver: bye..damn these engineers are so wierd man
@@TheWilferch It could, do... It would have needed more than Talladega: www.roadandtrack.com/motorsports/a29517421/mark-donohue-porsche-917-talladega-record/
@@therrydicule ...I know that effort...and look....even that car with 1200 hp...did what?.... a 220-225 mph?,....maybe hitting 240 on the straight?. The car had a CanAm body, where downforce was necessary, and the car had an enormous frontal area....it was wide with large Cd or drag coefficient. Here's a factoid for you and others to chew on.....the needed HP to get to a certain speed, increases with the CUBE of speed. Yes....raised to the "third power". If this means nothing to you from a math standpoint....let me use an example. A good 911 can hit 150 mph with 200 HP. To go just 50 mph faster, ...to hit 200 mph....it will need about 470 hp. Think this thru....we can't say "coulda-woulda"...the fact is ....it didn't.
@@TheWilferch Dr Helmut Marko and some other old dutch guy raced le Mans in the past as collegues ( he told on tv recently while having dr Helmut Marko on a live feed.) and they said, they did reach 400km/h back in the 70ties'. the 917 turbo had over way 1000 HP
This was really interesting. I initially thought it was pressurized to increase rigidity like the fuel/oxidizer tanks in a rocket. Cool concept to ensure chassis integrity though.
I'd thought the same, and even if that wasn't used in this I wonder if that could be used? In a lot of structures rigidity and strength in compression is a much bigger challenge than in tension. I could imagine a large thin structure pressurized with gas (possibly even helium - wouldn't float but a large structure at high pressure it could possibly save a few kilos, and in a case like this every gram counts) with the result that the material itself - probably ultra-thin carbon fiber - only has to be strong and stiff in tension. Sort of like a high-strength high-pressure balloon, we can think of balloons and other inflatable things as ultra-lightweight things with no stiffness whatsoever until inflated, this would have some but far less, becoming much stronger and stiffer when inflated. Only issue I could see is safety and reliability, the safety rules might not like it. Basically if a big hole rips in the car, it suddenly looses all it's strength and stiffness, leaving the driver surrounded by little more than floppy bedsheets at 200 mph.
Don't know about the Porsche but the Concorde is G-BSST, one of the prototypes, and it's at the Fleet Air Arm museum in Yeovilton, England. In that photo shoot it's pretending to be G-BOAF, the last to be built and the last to fly. It's fascinating to look around especially with some of the test equipment still on board. There are videos of it on UA-cam :)
Large cranes and draglines use pressurised tube frame for rigidity. The pressure is carefully monitored to signal cracks in the structure. The pressurised gas and the surface coating are chosen to react with one another, so the cracks are revealed with a surface colour change at the site of the crack/leak.
How safe is that? You get burns from scalding oil and broken bones when you crash because the hot oil runs through the chassis and the cars create lift but that being said what a monster!
I mean, when a crash is severe enough to break the chassis there wouldn't be much left of the driver either, as they sat so far in front that their feet were in ahead of the front axle. And there wasn't a crumple zone. If I remember correctly it was Richard Atwood who said that a slight shunt into the pit wall would've been enough to break both of your legs.
This video did a poor job of delineating the model that had the very bad aerodynamics. It was the very first version of the 917. To race the car Porsche had to produce 25 cars for homogenization. One privateer said the car scared him to death. He died on the very first lap. Note: that was the very first version of the 917.
"Porsche 917 - Wikipedia" en.m.wikipedia.org/wiki/Porsche_917. In the 1973 Can-Am series, the turbocharged version Porsche 917/30 developed 1,100 bhp (820 kW).
@@sandybarnes887 ...totally different car. No endurance-racing-trim 917 ...the closed coupe cars.... EVER had 1000 HP. Started with 520 in 1969 and ended up even after 2 size changes ( from 4.5 liters....to 4.9....then to 5.0)....never got over 560, maybe 600 HP. The turbo cars are also over-rated by urban legend...yes, on a dyno maybe hit 1500 momentarily, but ran races under 1000 HP.
I was fortunate to have a few words with Derek Bell at the Goodwood Festival many years ago. We were standing by the Gulf 917 and he clearly loved the car, saying you could comfortably take both hands off the wheel at top speed on the Mulsanne straight, it was that good. Lovely chap too.
Was the original 917 with no flies and bugs at the rear the LH and the shorter, open ended one [primarily featured in the footage you use] the K which was 30mph slower but dominated overall?
@@Timinator62 I heard the officials were bought out by Ferrari..... Andretti was second.... It was there first prototype win in years so they made sure of it....
I think it would have helped to have shown the difference and pics between the original 1969 car that had the handling problems and the kurtz tail that the video showed almost exclusively. It was after the '69 season was over and Porsche was creating the spyder with John Wyere that they came up with the short/raised tail. And, as they say, the rest is history.
Actually, Ford withdrew from the series when the FIA reduced engine displacement to three liters for prototype cars (Group 6) and five liters for "production sports cars which had at least 50 chassis made (Group 5). The Ford GT-40 MKII and GT-40 MKIV that won Le Mans in 1966 and 1967, respectively had 7 liter engines. Ford's entire racing program was rendered obsolete by the stroke of a pen. Ferrari’s 4 liter 330P4 was also made redundant by the new rules. Group 5 was intended to consist of Lola T-70s and Ford GT-40s with 5 liter engines. Group 6 would consist of the Alfa Romeo T33/3, Ferrari 312P, Matra 650 and Porsche 908 which all had 3 litre engines. The FIA did not anticipate that Porsche would produce 50 5 litre 917s... There are impressive photos of the cars lined up for the FIA to review. BTW, John Weyer's Gulf team beat at Le Mans Porsche in 1968 and 1969 using Ford GT-40 chassis 1075. Porsche hired him to run their team for the 1970 season. It was actually John Horseman on Weyer's team that determined the issue with the rear deck of the 917 after observing Jo Siffert driving the 917 PA intended for the 1969 Can-Am series. The PA was an open cockpit car and didn't have the long, tear drop shaped tail of the normal 917. The Gulf team mocked up a new tail and it worked very well. Thus was born the 917K.
Like the other guy said. Helium has a tendency to leak through things even without a crack so wouldn’t be ideal. Also nitrogen would be much cheaper and easier to get. And the difference in a helium filled chassis and a nitrogen filled one would probably only be a pound or two. You could save that weight easier by sending the driver to the bathroom.
I personally saw this car dominate in 1971. A Pedro Rodriguez driven 917 won at the 24 Hours of Daytona even though it spent over 1.5 hours in the pits replacing the transmission. It was that much better than any competition. Rodriguez drove this car like a maniacal maestro.
holly shit i was just watching vids on this car and spent all morning playing it on AC andd now you upload a vid of it.. wtf man stop spying me, not cool... but cool vid tho
Absolutely right. I came here to make the same comment and saw yours with a quick scroll through. There were only a couple of glimpses of the original long tail that was the problem in the video, and he certainly didn't make it that clear this was the one with the issue.
Pretty sure this car had around 600hp, not 1000. The Can-Am turbo 917s had 1000hp+, some say as much as 1500hp, but not the NA cars. 600hp was still a very impressive number for an NA 4.5 liter engine, in 1970. Also, particularly in the early 917s, the chassis were extremely flexible, which accounted for much of their evil handling nature. I love this car, it's one of my favorites of all time, but Porsche's reliance on the technical tricks mentioned didn't produce a sound chassis. It took bigger balls and greater skill to handle this beastie than it really should have.
Porsche didn't recognize the fly spatter aero problem. It was the Wyer team...notably John Horsman who did. The front of the car was splattered with bugs and flies at the Osterreichring in fall of 1969 testing....and the original long tail....even with the rear corner "flaps" in a total ( ! ) straight up position (!)....they were totally clean. Meaning, the air wasn't even contacting them. That night the rigged up plywood and tin and made a large kick-up tail...and the car was transformed....immediately more stable and soon 2-3 seconds PER LAP faster. This was the genesis of the 917 "K" which appeared in Daytona at the start of the next season....and won.
Pedant's corner: pressurised, *NOT* inflated, which surely would make a better, alliterative title: 'The Porsche with a pressurised chassis' Inflation - _literally_ by definition - means the object being inflated is distended by air or gas: if the chassis was that weak they'd be in real trouble... Came here hoping to learn something new on a deep dive about a fascinating detail of a legendary racing car, what I got was muddled ramble about the 917 generally without clear context or history, generally & of even evolution of the 917 itself: there's a section on the 917K at ~10mins - but that's virtually _all_ that's shown throughout the whole video. Isn't the paid promotion actually _longer_ than the bit actually teased in the title? It's also a separate section / chapter which the relevant bit isn't. 3 out of 10
A little misleading about the horsepower claims. The Lemans cars never came close to 1000 horsepower. Those numbers came about when the turbocharged 917/10 and 917/30 Can Am cars came along. My recollection from that era was it made under 600 hp in endurance racing mode and was severely out powered by the can am engines of the era that were around 700 horsepower. My favorite car of the era by far but by that time Enzo had lost interest in endurance racing and the very limited support of the 512m was proof of that. Roger Penske built a 512 that was faster on 3 separate occasions in a very limited schedule during the 917k models season. Ferrari spent the time developing the 312 for the following seasons rules and they dominated the next year. It would have been great to see the two teams slug it out for both of the 917 Lemans cars seasons but that didn't happen.
WHERE you got this Nitrogen story from I dont know.I was a mechanic on the 917 i n 1 1970 andg never saw a nitrogen cylinder.The chassis did a lot more than one race.The chassis were pressurised to check for cracks with an airline from a compressor.
Vasek Polak Porsche on US1 in Redundant Beach CA had six 917s in their show room. As a 19 year old engineering student at USC who happened to live less than a mile away, I would go a drool on them. Finally one day one of the salesmen got to talking with me. They used to let me sit in them and I was just this side of going comatose. The cars are TINY. They look large - at least to my eyes, but they are nothing of the sort. They are basically all engine. Those were some of the better memories of my young life. The dealership is gone now. Shame. I wonder whatever happened to those 917s.
The "Aluminum Balloon" structure was actually pioneered by Wernher von Braun for the German V2 program, was later refined for the American space program through out the 50's and 60's and is still used in modern rocketry today.
1. Opposed engines are not narrower. 2. The nitrogen was to detect a broken frame due to it being so weak... shades of Colin Chapman.....and done AFTER creaks showed up after 1st race. Original version, before John Weir team got their hands on, was a death trap.
Engineers: Of course, run hot oil through the spaceframe itself! Simple, elegant, no downsides.
Drivers: HELLO, THIS IS LITERALLY A TOASTER NOW, AND I'M THE BREAD
had a good chuckle when he explained that part.
"why the hell would they discard it?"
"oh."
i honestly thought it was a genius space and weight saving. totally forgetting that someone's actually driving it.
Not sure why we are getting excited about the oil running through the chassis to the oil cooler. Pretty much every race car of that period did that. Only stopped happening when the sport moved to monocoque chassis'
@@psk5746 mass-production motorbikes also, eg. some Buells used the frame for the fuel tank and (I think?) the swingarm for the oil tank
@@jsleeio true. Clever stuff. Quite like those bikes, even though I'm not a fan of the engine choice
My 450 dirt bike uses the frame as an oil tank... Didn't know in the beginning and burned my hand on it 😂
That was my first model car as a kid. Seeing it still gives me a special feeling.
Great video! I always wondered why no one makes a Porsche 917 continuation, especially when GT40 continuations have been so successful.
RCR makes a continuation. Only issue is your engine options are limited unless you manage to have an original flat-12 lying around. Cobras, GT40s, and even Lola T70s have the advantage of numerous V8 options. Personally, I wouldn't want a 917 replica with a 911 engine or a V8 stuck in it.
Im really loving these informative race car engineering videos. They are addicting.
You sir are the master of the sponsor transition. Well played yet again
They were oppsessed with lightness , The gear shift lever knob was also made of Balsa Wood which is very light and mainly used for RC model Planes.
Porsche got inspired by Lola T70 rear shape in order to create downforce in the rear axle, and it worked the car no longer swerving in the straights so much.
The only producer as smooth with their transitions to sponsors/merchandise than Driver61 is 3Dbotmaker.
that ridge ad was real smooth lmao. respect
Per _Porsche 917_ (by Gordon Wingrove) [page 58], the bug-spatter discovery/downforce solution did not come from Porsche, but from John Wyer's engineers at JW Automotive (who Porsche employed to sort out 917 problems and to make improvements). Book excerpt [my inserted comments are in brackets]: _After some tyre testing, the Wyer personnel were invited to become involved_ [with the 917's aerodynamic issue]. _John Horsman_ [JW Automotive Engineering Manager] _was well-acquainted with high-speed aerodynamic problems, having been instrumental in using spoilers to stabilise the early design of the GT40. He spotted that while the front of the coupes were covered in dead flies and gnats, the rear spoilers appeared to be clean except for the very top edge -- which indicated that the airflow was mostly passing above them. After a group discussion between both the Porsche and JWA engineers and with some dimensional input by John Horsman, Cuoghi_ [JWA Chief Mechanic] _and Davies_ [JWA Mechanic] _then set about building a rear 'deck' for_ [chassis] _008._ [Note: The 'deck' was effectively the "boilerplate" for the rear-end fix that resulted in Porsche/JWA joint development of the 917 short-tail version, i.e., the 917K.] _Brain Redman went out to try a couple of laps in the_ [modified chassis 008] _car -- and stayed out for more as he gained confidence in the handling. When he came back to the pits he is quoted as saying 'now you can_ drive _the car..._
They should place fluids in the frame maybe not fuel though. Oil or maybe a very inert coolant.
The level of engineering was insane. The text on the tyre heater 'remove before flight' a little foreboding! The cooling fan atop the engine like like a tyre rim.
PS, yeah I got to that part now. Never crossed my mind about cabin heat. How was the frame filled with nitrogen and fluids? Or was the pressure monitor removed for the fluid frame?
The 917 wasn't the first racecar to use a pressurized tube frame. Don't remember who had it first. Maybe Lotus. Also they would pressurize the frame and put it in a swimming pool, looking for bubbles.
It's actually very difficult to save weight replacing steel with aluminium as aluminium does need more material to give similar strength conpared to steel.
Only when going for Magnesium alloys the balance shifts in favour of the lightalloy .
But the there is Titanium , just as delicate and elaborate to work on .....
The Kauhsen 917 LeMans winner was ,according to Willi K. himself one of the very few 917 chassis made from magnesium alloy tubing ....
I wonder if they could have fixed the problem of the air detaching from the car by adding small plastic vortex generators to the top of the car. Works wonders on airplane wings to keep the airflow from detaching!
Nitrogen doesn’t react with the metal due to displacing oxygen preventing corrosion also it’s a dry gas that does not react much to temperature causing a pressure rise or fall. That’s why we use it in HVAC
Here's an idea. Instead of pressurising the tubes, create a vacuum instead. Alerting to failure if air re-enters. This would also save a little more weight no?
that sponsor plug was smooth
Imagine how rediculous it would be to have a chassis health barometer on your car
hehehe
good one
*going fuckoff fast on the straight with the sky in the rear mirror*
Suddenly the pressure in the chassis starts dropping...
Bet the drivers paid most attention to that gauge
Not ridiculous at all. The same basic system (except with compressed air) is used in many tubular structures that rely on weld integrity for their strength - crane and drag line booms, for a start.
Actually...aeroplanes have this too (sort off)
All that nitrogen must have helped with 'the bends'.
Lol
I dislike that I liked this comment
Wat?
haha nitrogen go brrrr
Oh shit! High IQ stuff here!
Up! movie: Strap balloons to a house
Porsche: **Makes the car a balloon**
They could have filled it with helium and it would have been even lighter.😂
@@tanmayta9131 Yeah, some gases are reactive/explosive
@@RacingLegendss Yes, but helium doesn't react or explode cause it is inert.🙂
The car flew around the track literally and figuratively
@@getnaenaed4222 that’s true hahahaha
Porsche is arguably one of the best car manufacturer in the world. They've build a chasis lighter than my whole body
Insane when you put it that way
Definitely not arguably..
Thats basically all what they do, mercedes not only makes cars but also trucks, bus, bulletproof cars.......
Unless you are a child, that's good news for you I'd say.
Well I'm a BIT underweight, I'm only 3 kg heavier
Only thing I would like to add is km/h alongside with mph for us who aren't familiar with mph. Otherwise it's once more a great video, I love this kind of content about engineering and mechanics and you explain everything so well Scott! Thank you!
Feedback noted, thanks for commenting - glad you liked it!
Yes would be a help. I just convert to kph in my head .
Here : mph to kph 10 mph = 16.1 kph
1.6kph to 1mph
62.xxx mph is 100kph
@@Driver61 if you are keen to receive feedback, i kinda wanted to close the video halfway because the way you edited your speech, you didnt leave ANY space at all, its like reading a sentence without commas or periods, it felt weird, also, this could be just be me, but the pace is also weird, it goes like this "but not every sentence NEEDS to have HIGHLIGHTED wordsFOLLOWED byfastwordsthatendin s l o w w o r d sONLY to not LEAVE any space BETWEEN senten c e s"
Tl:dr: a small break here and there, in my opinion, would make it sound a lot more natural.
Edit: i did enjoyed the video though, excelent investigation, presentation and footage (:
and put things in lbs because I don't know kilos
Who would have thought Helmut Marko won Le Mans in a 917k
I would never!
That was before he lost vision on one of his eyes, it was when he was racing in F1 at Clemont-ferrand when he got involved in a crash.
Probably people who read...
so it was a stone that flicked up into his visor from the lotus in front that ended his career? :O oh yeh he also set the fastest ever lap on the targa florio. record never broken.
marko in 72... ua-cam.com/video/pF_oF-ZMhD0/v-deo.html
5:35 "... they pressurized the entire space frame with nitrogen..."
Having indication of cracks it's not the only and probably not the most important benefit of pressurizing the space frame.
Pressurizing a space frame allows you to use thinner material yet still avoid buckling. think of how you could stand on a full can of Coke, but there's no way a depressurized can would support your weight.
The Atlas missile also used this method to avoid buckling while saving weight. doesn't even take that much pressure.
so well it may have provided a convenient indication of any cracks, the main benefit would have been the ability to use thinner gauge tubing.
Actually, a can would hold your weight, if you were able to apply the pressure evenly. The cylindrical form is key there.
@@noneofyourbusiness4294 In real life standing on a soda can and certainly in real life in the frame of a race car pressure is never applied evenly.
In real life, thin world tubes are subject to buckling instabilities. To close approximation, thin wall tubes of the same external dimensions differing only in wall thickness will exhibit the same stiffness until the point the wall buckles.
pressurizing the tubes isn't some afterthought or just a check for leaks, It is fundamental to the strength of the frame.
@@bengriffin4027 the nitrogen is still a gas though so it's compessible. even if it may help resist buckling a bit, the amount of gas displaced when a tube collapses only raises the gas pressure in the entire frame by a bit. Don't forget soda can's are filled for more than 90% with an incompressible liquid meaning a small change in internal vollume greatly compresses the tiny bit of gas at the top, proportionally speaking. The Atlas rocket was also filled with liquid propellants and when these propellants were drained from the tanks as the rocket went up, the weight of the rocket also decreased so the airframe was less stressed allowing the airframe to better support itself. Besides that, the propellant tanks had different length/diameter proportions compared to the 917 frame which allowed them to act more like a balloon. (same goes for the soda can)
Lets add a large impact to said full can of coke.... Not only does it crack or buckle... It will blow out significantly.
@@ddewaard3265 Indeed. The compressibility you raise is a very good point, and even if that were not the hypothesis-killer it clearly is, the soda can analogy has another flaw: the relative wall thickness of a soda can (as a proportion of tube *diameter* ) is several orders of magnitude less than in a chassis tube of maybe 16 to 20 OD x 2.0 wall.
To provide meaningful anti-buckling support in the latter case would require ridiculously high gas pressures, which would cause the elements which were right-sized for tension forces past their failure point.
In any case, the valves for filling the tubing with gas (which is generally understood in the engineering community to have been air rather than nitrogen in the case of these cars) were nothing more than conventional Schraeder valves, hence completely unable to hold the very high pressures anti-buckling would require.
This is becoming my fav car channel,technical minutae perfectly explained for the layman
Yea agreed! Love these videos.
When Lotus said add lightness, Porsche did it literally.
Damn! that transition to the sponsor was HELLA smooth!
Agreed that transition was impressive. Lol
He’s been getting real good at it, his last 3 videos all had super smooth sponsor transistions
And it was quick, to the point, and something actually cool instead of some of the obnnoxious garbage most sponsors tend to be [*cough* bRiLlIaNt *cough*]
@@camillecirrus3977 😂
almost felt like the entire video was done for this sponsor lol
The pressurized nitrogen is an ingenius solution. Simple but effective.
Putting the 1000 horsepower engine, in the most fragile chassis possible and doing fuck all about the aerodynamics however was not.
@@paulzapodeanu9407 They debugged it eventually. Thank the insects for showing them where the flow was separated.
SIMPLE???
@@craigykart Yes, but maybe test the car BEFORE the race.
Maybe helium would of added lightness
"I'm a doctor"
"Oh, what kind?"
"I operate vehicles to victory"
Valentino Rossi
That reminds me of a joke. There's a car accident accident and someone shouts out "is there a doctor around here? It looks like the driver is going to die!" Someone says "I'm a doctor of philosophy- everybody dies!"
good one, even though he is a doctor in law.
@@oxcart4172 I don't understand
@@cpawel if u have to explain a joke to someone they're not going to think it's funny.
Is it just me or does the old Gulf oil livery make any and all cars look pure sex? Martini too.
Martini for me
they are good, aye.
Those are awesome on the right car the 555 and sometimes Marlboro too if it fits hIsToRiCaLlY
@@Moto_Medics Ooooh. I forgot all about Marlboro. Good pick.
John Player special is another good one
that weight is impressive, I work with solar cars who have a Carbonfiber monocoque, and 42kg is still really light even for composites
Do you do your torsional test your solar car chassis?
Do you do them in autoclave or out of autoclave
Downside: Drivers required balls of steel, which added weight.
The "aerodynamic development by flies" did not happen at Le Mans. It happened at the Osterreichring old circuit during a test session. Porsche had contracted with John Wyer Automotive Engineering, who'd beat them twice at Le Mans with Ford GT40s. John Horsman was Wyer's race engineer, and he attended a test session in the summer of 1969 to get a look at his new charge.
When he arrived, the Porsche team were chasing handling gremlins. They'd make an adjustment, swop parts, etc. then send test driver Willie Khausen to do a couple of laps. When he came in, they'd ask his impression, compare lap times, etc. Nothing worked; no matter what they did to fix the handling, the result was always, "no improvement," or "it's even worse."
When the team took a lunch break, Horsman looked the test 917 over, carefully. That's when he discovered that the bug splats hitting the front of the car, as expected. But curiously, there were almost none, past the doors. He also spoke with other drivers testing other cars and discovered that they preferred the greater stability of the short-tailed cars to the nominally faster long-tailed, stream-lined ones.
After testing ended for the day, Horsman asked the Porsche engineers if he could borrow some sheet aluminium and the team's second 917 chassis. That evening, he and his chief mechanic cut up the aluminium and duct taped it on the car, creating wedgy box that covered the rear wing to roughly the top of the cockpit height.
Next morning, Khausen took the modified car out for a drive. The Porsche crew expected him to return to the pits after a couple of laps. Instead, he kept on going. When he finally did stop, the engineers asked why he didn't stop. Khausen looked up at them and declared, "Finally, this thing is a RACE CAR! Now we can work on it." Horsman's "box" was refined into the wedge-shaped tail the 917 was famous for, and the rest is history. And a Steve McQueen film.
Ultimately, Porsche did get the long-tailed 917 to work by raising the rear wing and re-sculpting the tail to reduce lift, but it's John Horsman's on-the-spot improvisation that made the car a winner.
Great information!
Can you please share the source with us? Book, magazine, journal?
I would like to learn more about this history.
Interestingly, in a recent interview the other Porsche works driver present, Kurt Ahrens (also the winner of that 1969 Austrian grand prix with Jo Siffert), says it was basically him who came up with the idea, which would have to do with his family business, a metal-selling/scrapping company, in which he was constantly playing around with scrap as a kid, making his own cars. He was passing through the formula classes for Brabham, battling in Formula 2 often successfully with Clark, Hill, Rindt, Ickx... while being his own mechanic as a privateer (financed by his family business), and was known for having enormous mechanical empathy with the cars, the kind of guy who'd notice right away that the rear left wheel is slightly out of alignment or that the dampers were on their way out, and would have an idea how to fix it immediately; also he never crashed a single car during a race, known as a very rational and disciplined driver, so he was hired by Porsche to help with 917 development, a difficult job he was extremely well suited for. He suggested to the engineers to get some aluminium sheet from the hardware store in nearby Knittelfeld he had noticed on the way, and simply sticking it to the rear to see what that would do, the kind of thing he'd do to his own car; and it was applied that same day (perhaps after coming up with it independently after considering the fly-splatter-pattern, who knows); the brits ran with the story ever since. He's one of the more humble, shy and down-to-earth characters in racing, certainly not into fame and recognition - actually turning down driving F1 for Brabham after one race as he figured, this F1 circus with worldwide races wouldn't allow him to be with his family and the business anymore, and he's quite rare to give interviews. He says he asked Piech and Peter Falk soon after the 917 story if he should offer a correction to that story to the public, but it was suggested after a bit of quiet consideration for him to keep quiet, as that story would play better with the international audience if it were the british, making the 917 a more international project so to speak... I would say, that would be entirely in line with what is known about Piech and his strategic mind. David Piper who also partook in in that Austria 1969 race confirms that story.
Oh, and the other guy's name is spelled Willi Kauhsen, if someone wants to look him up. If he had told that sort of story, I probably wouldn't believe a word, he's a great character and absolutely entertaining to listen to, but definitely a story-teller never shy to "emphasize" his own role in whatever happened. Ahrens is a very different character. In fact, it doesn't matter too much who actually came up with it first - they had a lot of brilliant and highly motivated minds pulling all-nighters and working their ass off to get this car right.
@@decnet100where do you got this info from. I guess a certain podcast maybe? Alte Schule?
@@z33r0now3 Sure, the interview with Ahrens there is the longest that he has given (in public) to my knowledge, other than the interviews he did with his long-time friend Eckhard Schimpf for his book ("Einer dieser verwegenen Kerle") which is also a good source on his involvement in 917 development.
At any rate, I find it hard to believe that the often-quoted fly-pattern actually tells so much useful information, at least not in the way it is most usually mentioned about the 917 (lots of flies in the front, no flies in the rear, ergo bad airflow on the rear) - I'd expect that the rear on any car, even several ones with very much working rear aerodynamics will be comparatively clean of flies and other debris as the impact of those particles will mostly happen around high-pressure spots such as the frontal area, not an area of laminar flow as you'd want along even an effective downforce-producing body section at the rear. With the early 917 tails that they ran, the only part where I'd expect any splatter would be the vertical stabilizer, perhaps that's what they meant.
I'd hazard the guess that the decision to let this be claimed by the brits was also influenced by that fact that at Porsche there were several big heads (which may have included Piech himself) who held the "streamlining" concept in the highest regard - as is logical for a company used to bringing small-engine cars to Le Mans, one of the fastest races there was; their natural instinct in terms of aerodynamics would be to run as clean as humanly possible. I'm sure there was some hesitation to "ruin" the car in that regard with that rear spoiler section, which held back the performance initially - and even if the problem was known to several people including Ahrens, the situation may have required an external actor to pass..
@@decnet100 interesting comment. Food for thought. Thanks for replying. I drive the 917k in a simulator on the nordschleife in Virtual reality. It’s my fav race car besides 908/956/962. it’s not the real thing and it’s already so bonkers to hold the car on the track, makes you appreciate how hard it really must have been.
Germany be like: “Ich muss den Motorsport dominieren”
Mein got muss da sein
@@joshgee8714 so ein Bockmist aber auch.
@@joshgee8714 Mein Gott, muss das sein?
@@dj1rst exactly
Get ready for Germans without sense of humor
Ferrari and Ford arguing about who’s gonna win*
Meanwhile in Germany at Porsche hq: ok soooo we gonna do the frame that is light as flip and win
The Ridge wallet. THE state of the Art when it comes to slipping, falling and having your wallet break your hip
7:50 In the picture it's the 917K which has the correct
aerodynamics. It was actually the prototype 917 with a sloped down tail that's unstable. That's why the later 917s have a raised bodywork towards the end and often some small deflectors to achieve more downforce. Apart from that you are explaining it brilliantly. Great respect to you! 👍
Just a correction the 917 that raced at Le Mans produced around 650 hp the Can Am racers that raced in America aka the 917/30 could produce 1000 hp
917/30 can-an
Was able up to 1200hprs at max Turbo setup and weight around 800 kg.. OoF
There are "some" (toooooo many) other Facts he did wrong.
Mostly everything about the 1st longtails and that K just means kurzheck / shorttail and so on.
"Porsche 917 - Wikipedia" en.m.wikipedia.org/wiki/Porsche_917. In the 1973 Can-Am series, the turbocharged version Porsche 917/30 developed 1,100 bhp (820 kW).
917/10 TC 1000 PS
917/30 Spyder 1100 PS (Racetrim)
917/30 Spyder 1570 PS (Fullboost 2.24 bar)
Holy crap! Always loved that car but never knew the details. Sounds like the Star Wars films. Long ago in the past but somehow far in the future.
Big thanks to Ridge for sending me this wallet and supporting the channel! Find a link in the description to get yourself 10% off!
Weight saving level 100! Who would love to have a go in this iconic Porsche? Hope you're all glad I pronounced Porsche correctly this time!
NOTE FROM EDITOR: We're very aware we show the 917K when talking about the 917, however there is very little good footage of the 917 out there. Given most people wouldn't be bothered by this detail, we used the 917K footage. But if you spotted it - 10 brownie points to you.
Me!
Great video, as always. I do have to get used to your Imperial System. Could you at least put the speeds in km/h as text on screen if you do not want to mention them please?
1 - The 917 has a 180 degree V12, not a flat(boxer) engine. In a V engine opposing pistons share a crank pin, in a boxer each piston has their own pin.
2 - Another neat thing about the 917's engine is that in the middle of the crankshaft there is a gear that connects to an intermediate shaft that drives the flywheel and ultimately the car. This essentially halves the flex the crankshaft has to withstand, which in a 1000-1200 bhp long V12 engine is quite a good idea.
As an engineer, I like this kind of details.
@@Jacob-W-5570 I actually thought it was a neat idea as well when I saw an engine cutout at the Porsche museum in Stuttgart. Definetly worth a visit if your close by. Though the Mercedes museum in the same city is much, much better.
I am happy you mentioned that. It is my assertion that taking the drive at the minimum first degree node of flex allowed the use of smaller crank bearings resulting less internal drag on the crankshaft. I.e. less parasite engine drag allowing the power that would be lost to drag on the crank to be used to propel the car.
It is still considered a flat 12, just not a boxer
True on the center power take-off on the engine.....and here's another 917 tidbit......the mating gears have a "hunting" tooth.....one gear does not have the same number of teeth as the mating gear...so the "Same-two" gear teeth don't mesh with every revolution. So an interesting question emerges.....when you see the RPM of this engine, is it the crankshaft speed or the slightly different output shaft ( clutch) speed......oops .....time's up. Cheers !!!
John Wyer and/or David Piper solved the aero issues as David had a Lola T70. Note the rear of a 917 was changed to being almost identical to a T70
John Wyer's team....specifically led by John Horsman during Fall 1969 testing in Austria..... solved the aero issues.
Marko's teammate was a Dutch guy, Gijs van Lennep
Some of the most advanced techniques at the time:
Porsche: haha ze bug goes splasch
As often as you see him in the RB paddock during the F1 races, you tend to forget Helmut Marko has had some incredible motorsport accomplishments of his own.
Porsche: all in the name of saving weight
Ken miles: WHAT?
"V12 Nah,Flat 12". well it is a V , 180 degree v12
theres a difference between flat v and boxer
@@mathias6369 Yes, but the 917's engine wasn't a boxer.
I lost brain cells reading all 3 of these comments
@@ProVision3187oh yeah? i just repeated the sentence that was written in the video and corrected it. other guy said there are differences between 180 deg v engines and boxers which is true , and the second guy said 917ks engine wasnt a boxer which is also true. so what the fuck are you even talking about
Ryan Miller wrong , flat means both boxer engines and 180 degree V engines. They are called 180 V because their arthitecture is same as a V engine. In a 180 V engine 2 pistons from opposite banks share a rod journal (crankpin) and move together. Where as in a boxer engine each piston gets its own rod journal and therefore isnt connected to the cylinder at the opposite bank and dont move together. In fact they move in opposite directions to each other.
That transition into the ridge wallet sponsor 👌 👌👌
*shows picture of concorde, which was aluminium* .. talks about Ti.
Mhmm.
@@craigykart Still had Titanium components, just like he said.
Amazing video ( as ussual). Just one complain: Please try including logical meassuring ( aka metric system) Cause pretty much no one - but the US and a few other non-logical nations- uses Imperial anymore. Thank you
At first I thought they pressurizing it for better stiffness,like pressurized soda cans :))
Same here
0:32 Hate to be pedantic, but the 917k made about 600 bhp, the 1000+ bhp ones were the 917/10 and 917/30 turbo cars built for Can-Am
Watching Steve McQueen's Le Mans really adds to the mystique of the 917. It's truly an amazing car
Buttery smooth transition to the sponsor (and back). Wasn’t annoying, how it should always be done!
I've had the pleasure of watching the 917K race at Laguna Seca a few times. It really is an incredible piece of machinery.
Ah the Germans annoyingly good at almost everything when it comes to making cars and virtually every other aspect of engineering they reign supreme
It should also be noted that this video is primarily focused on the original , coupe 917 used for endurance racing as for LeMans. Engines were 4.5 liters....later 4.9 liters...and finally at 5.0 liters. Horsepower went from 520 to close to 600. What is missed here, is that all this engineering and details, are also found in the previous racing models,where the 917 is the culmination of this evolution of the series. The 906, 907, and especially the immediate predecesor 908 , had the same frame design and nitrogen pressurization. Even the basic engine design of the 908 was "Somewhat" carried over, as 908 only had an 8 cylinder engine, at 3 liters size.....it was "basically" the same as to items like pistons and connecting rods ( 12/8 x 3 liters = 4.5 liters.....the original 917 engine size). The 908 had around 350 hp so the estimate of 520-525 for the original 917 engine translates reasonbly well, too.
Nice story!! Instead of a wind tunnel, just check to see where the flys end up. That's a good one. 😆
They eventually had to use a wind tunnel for 1971.
porsche engineer: so how is ze car? very fast yes? is good?
porsche driver: oh it's fast alright, it's actually scary at times but i'm sure all the safety features will keep me safe right?
porshe engineer: ze what now?
porsche driver: safety features?
porsche engineer: ah yes *looks around nervously* we've made this of course
porsche driver: i mean it gets so fast at times i feel like i would die instantly if i crashed haha just joking
porsche engineer: *nervous laughter* haha yes well alive dead who are we to say, maybe it's all a simulation i mean am i alive right now? are you alive? what is life even you know
porsche driver: ...what do you mean?
porscheengineer: oh don't worry just being silly...driver who accepts the terms and conditions of the contract that clear the porsche engineering team of any liability in case off a fatal crash says what?
porsche driver: what?
porsche engineer: gotem, oh wow would you look at ze time i have to go now to work on these safety features that are totally real, don't forget to hug your wife before ze race yes? for good luck...bye now
porsche driver: bye..damn these engineers are so wierd man
I did just this week a presentation on the porsche 917, what a great video man keep it up.
Where did ya present it bro
The triangle contact point is also called Truss, those things are tough af
"With top speeds similar to F1" ? Dude! with over 400 km/h the 917 was much faster than F1 at the time !
Urban legend...no 917 ever hit 400 km/H ( 250 mph). www.mulsannescorner.com/maxspeed.html
@@TheWilferch
It could, do...
It would have needed more than Talladega:
www.roadandtrack.com/motorsports/a29517421/mark-donohue-porsche-917-talladega-record/
@@therrydicule ...I know that effort...and look....even that car with 1200 hp...did what?.... a 220-225 mph?,....maybe hitting 240 on the straight?. The car had a CanAm body, where downforce was necessary, and the car had an enormous frontal area....it was wide with large Cd or drag coefficient. Here's a factoid for you and others to chew on.....the needed HP to get to a certain speed, increases with the CUBE of speed. Yes....raised to the "third power". If this means nothing to you from a math standpoint....let me use an example. A good 911 can hit 150 mph with 200 HP. To go just 50 mph faster, ...to hit 200 mph....it will need about 470 hp. Think this thru....we can't say "coulda-woulda"...the fact is ....it didn't.
@@TheWilferch Dr Helmut Marko and some other old dutch guy raced le Mans in the past as collegues ( he told on tv recently while having dr Helmut Marko on a live feed.) and they said, they did reach 400km/h back in the 70ties'.
the 917 turbo had over way 1000 HP
@@TheWilferch
i guess you can apply for a job.
careers.mercedesamgf1.com/vacancies/
www.redbull.com/int-en/redbullracing/jobs
Best racing Channel on UA-cam. Period
And then Helmut came to F1 and said "hmm, what should we do today? Ah yes, drop every 2nd driver in Red Bull"
The 917 is my favorite Porsche race car of all time😃
0:30 C´mon ... it was never near 1000bhp in the original NA version.
This was really interesting. I initially thought it was pressurized to increase rigidity like the fuel/oxidizer tanks in a rocket. Cool concept to ensure chassis integrity though.
I'd thought the same, and even if that wasn't used in this I wonder if that could be used? In a lot of structures rigidity and strength in compression is a much bigger challenge than in tension. I could imagine a large thin structure pressurized with gas (possibly even helium - wouldn't float but a large structure at high pressure it could possibly save a few kilos, and in a case like this every gram counts) with the result that the material itself - probably ultra-thin carbon fiber - only has to be strong and stiff in tension. Sort of like a high-strength high-pressure balloon, we can think of balloons and other inflatable things as ultra-lightweight things with no stiffness whatsoever until inflated, this would have some but far less, becoming much stronger and stiffer when inflated. Only issue I could see is safety and reliability, the safety rules might not like it. Basically if a big hole rips in the car, it suddenly looses all it's strength and stiffness, leaving the driver surrounded by little more than floppy bedsheets at 200 mph.
The nitrogen solution comes from aviation, it was nothing new. Airplanes main spar are filled with pressurized N2 for the same reason.
4:29 "REMOVE BEFORE FLIGHT" One hell of flight that is.
I love that they used balsa wood to make the gearstick knob even lighter!!
5:49 where is that place? A Concorde and a 917 truly amazing image !
Don't know about the Porsche but the Concorde is G-BSST, one of the prototypes, and it's at the Fleet Air Arm museum in Yeovilton, England. In that photo shoot it's pretending to be G-BOAF, the last to be built and the last to fly. It's fascinating to look around especially with some of the test equipment still on board. There are videos of it on UA-cam :)
Large cranes and draglines use pressurised tube frame for rigidity. The pressure is carefully monitored to signal cracks in the structure. The pressurised gas and the surface coating are chosen to react with one another, so the cracks are revealed with a surface colour change at the site of the crack/leak.
How safe is that? You get burns from scalding oil and broken bones when you crash because the hot oil runs through the chassis and the cars create lift but that being said what a monster!
I mean, when a crash is severe enough to break the chassis there wouldn't be much left of the driver either, as they sat so far in front that their feet were in ahead of the front axle. And there wasn't a crumple zone.
If I remember correctly it was Richard Atwood who said that a slight shunt into the pit wall would've been enough to break both of your legs.
@@mikeblatzheim2797 true but if a line were to blow it could be really bad
This video did a poor job of delineating the model that had the very bad aerodynamics.
It was the very first version of the 917. To race the car Porsche had to produce 25 cars for homogenization. One privateer said the car scared him to death. He died on the very first lap. Note: that was the very first version of the 917.
Can you please provide all speeds in KPH too? People from all over the world watch your videos.
Erm, nearly 1000 horsepower? Genuinely curious, I've never heard that figure associated with the 917k that you're showing
"Porsche 917 - Wikipedia" en.m.wikipedia.org/wiki/Porsche_917. In the 1973 Can-Am series, the turbocharged version Porsche 917/30 developed 1,100 bhp (820 kW).
@@sandybarnes887 Yes, but in this video he is referring to the 917k that competed at Le Mans, and they only ever produced around 600.
@@sandybarnes887 ...totally different car. No endurance-racing-trim 917 ...the closed coupe cars.... EVER had 1000 HP. Started with 520 in 1969 and ended up even after 2 size changes ( from 4.5 liters....to 4.9....then to 5.0)....never got over 560, maybe 600 HP. The turbo cars are also over-rated by urban legend...yes, on a dyno maybe hit 1500 momentarily, but ran races under 1000 HP.
I was fortunate to have a few words with Derek Bell at the Goodwood Festival many years ago. We were standing by the Gulf 917 and he clearly loved the car, saying you could comfortably take both hands off the wheel at top speed on the Mulsanne straight, it was that good. Lovely chap too.
Was the original 917 with no flies and bugs at the rear the LH and the shorter, open ended one [primarily featured in the footage you use] the K which was 30mph slower but dominated overall?
And to think Steve McQueen actually raced one and won at Sebring....
That was a 908 and he didn't Win, he and Peter Revson came in Second....sheesh
@@Timinator62 I heard the officials were bought out by Ferrari..... Andretti was second.... It was there first prototype win in years so they made sure of it....
@@MiguelGarcia-vj7oo LOL Ok dude whatever
I think it would have helped to have shown the difference and pics between the original 1969 car that had the handling problems and the kurtz tail that the video showed almost exclusively. It was after the '69 season was over and Porsche was creating the spyder with John Wyere that they came up with the short/raised tail. And, as they say, the rest is history.
I know some people who think a Ford should have kept going at Le Mans into the 1970s. Now I know why Ford didn’t do that, lol
Actually, Ford withdrew from the series when the FIA reduced engine displacement to three liters for prototype cars (Group 6) and five liters for "production sports cars which had at least 50 chassis made (Group 5). The Ford GT-40 MKII and GT-40 MKIV that won Le Mans in 1966 and 1967, respectively had 7 liter engines. Ford's entire racing program was rendered obsolete by the stroke of a pen. Ferrari’s 4 liter 330P4 was also made redundant by the new rules.
Group 5 was intended to consist of Lola T-70s and Ford GT-40s with 5 liter engines. Group 6 would consist of the Alfa Romeo T33/3, Ferrari 312P, Matra 650 and Porsche 908 which all had 3 litre engines. The FIA did not anticipate that Porsche would produce 50 5 litre 917s... There are impressive photos of the cars lined up for the FIA to review.
BTW, John Weyer's Gulf team beat at Le Mans Porsche in 1968 and 1969 using Ford GT-40 chassis 1075. Porsche hired him to run their team for the 1970 season. It was actually John Horseman on Weyer's team that determined the issue with the rear deck of the 917 after observing Jo Siffert driving the 917 PA intended for the 1969 Can-Am series. The PA was an open cockpit car and didn't have the long, tear drop shaped tail of the normal 917. The Gulf team mocked up a new tail and it worked very well. Thus was born the 917K.
@@JanZizkaMetal Ah, I see. Thanks for the info! I’m not great when it comes to this Classic Le Mans stuff lol
@@mdewulf0922 Here's something you might find interesting.
ua-cam.com/video/j9XCEM4S2yY/v-deo.html
This car didn’t have 1000bhp. Nearer 600hp.
They could have filled it with helium and it would have been even lighter.😂
@Right Above You Helium and Hyrdogen have the bad property of leaking even when there are no cracks. Could've been part of the consideration.
Like the other guy said. Helium has a tendency to leak through things even without a crack so wouldn’t be ideal. Also nitrogen would be much cheaper and easier to get. And the difference in a helium filled chassis and a nitrogen filled one would probably only be a pound or two. You could save that weight easier by sending the driver to the bathroom.
I personally saw this car dominate in 1971. A Pedro Rodriguez driven 917 won at the 24 Hours of Daytona even though it spent over 1.5 hours in the pits replacing the transmission. It was that much better than any competition. Rodriguez drove this car like a maniacal maestro.
holly shit i was just watching vids on this car and spent all morning playing it on AC andd now you upload a vid of it.. wtf man stop spying me, not cool... but cool vid tho
You keep showing the 917k version when talking about the original long tail 917. And the animation is wrong.
Absolutely right. I came here to make the same comment and saw yours with a quick scroll through. There were only a couple of glimpses of the original long tail that was the problem in the video, and he certainly didn't make it that clear this was the one with the
issue.
That transition to sponsor was so good I now need a wallet.
Can I get a 917?
The only thing more streamlined than that car was that segway ^^
Great Vid!!
Pretty sure this car had around 600hp, not 1000. The Can-Am turbo 917s had 1000hp+, some say as much as 1500hp, but not the NA cars. 600hp was still a very impressive number for an NA 4.5 liter engine, in 1970. Also, particularly in the early 917s, the chassis were extremely flexible, which accounted for much of their evil handling nature. I love this car, it's one of my favorites of all time, but Porsche's reliance on the technical tricks mentioned didn't produce a sound chassis. It took bigger balls and greater skill to handle this beastie than it really should have.
Could you please do a video on Can-Am racing and or Porsche's domination with the 917/30?
Porsche didn't recognize the fly spatter aero problem. It was the Wyer team...notably John Horsman who did. The front of the car was splattered with bugs and flies at the Osterreichring in fall of 1969 testing....and the original long tail....even with the rear corner "flaps" in a total ( ! ) straight up position (!)....they were totally clean. Meaning, the air wasn't even contacting them. That night the rigged up plywood and tin and made a large kick-up tail...and the car was transformed....immediately more stable and soon 2-3 seconds PER LAP faster. This was the genesis of the 917 "K" which appeared in Daytona at the start of the next season....and won.
This design was insane 😳 or desperate 😝
I suspect pressurizing the chassis would also stiffen it.
Once again the smoothest ad transition ever
for real he is too good for us lol
Pedant's corner: pressurised, *NOT* inflated, which surely would make a better, alliterative title: 'The Porsche with a pressurised chassis'
Inflation - _literally_ by definition - means the object being inflated is distended by air or gas: if the chassis was that weak they'd be in real trouble...
Came here hoping to learn something new on a deep dive about a fascinating detail of a legendary racing car, what I got was muddled ramble about the 917 generally without clear context or history, generally & of even evolution of the 917 itself: there's a section on the 917K at ~10mins - but that's virtually _all_ that's shown throughout the whole video. Isn't the paid promotion actually _longer_ than the bit actually teased in the title? It's also a separate section / chapter which the relevant bit isn't. 3 out of 10
6:55 Dude made the smoothest promotion in the whole platform :0!
A little misleading about the horsepower claims. The Lemans cars never came close to 1000 horsepower. Those numbers came about when the turbocharged 917/10 and 917/30 Can Am cars came along. My recollection from that era was it made under 600 hp in endurance racing mode and was severely out powered by the can am engines of the era that were around 700 horsepower. My favorite car of the era by far but by that time Enzo had lost interest in endurance racing and the very limited support of the 512m was proof of that. Roger Penske built a 512 that was faster on 3 separate occasions in a very limited schedule during the 917k models season. Ferrari spent the time developing the 312 for the following seasons rules and they dominated the next year. It would have been great to see the two teams slug it out for both of the 917 Lemans cars seasons but that didn't happen.
That transition to ridge wallet promotion was so smooth, every objects in my room lost friction. Help, I cannot stop sliding
WHERE you got this Nitrogen story from I dont know.I was a mechanic on the 917 i n 1 1970 andg never saw a nitrogen cylinder.The chassis did a lot more than one race.The chassis were pressurised to check for cracks with an airline from a compressor.
No pictures of the L-model model, and showing the K-model when talking about the L-model????
Vasek Polak Porsche on US1 in Redundant Beach CA had six 917s in their show room. As a 19 year old engineering student at USC who happened to live less than a mile away, I would go a drool on them. Finally one day one of the salesmen got to talking with me. They used to let me sit in them and I was just this side of going comatose. The cars are TINY. They look large - at least to my eyes, but they are nothing of the sort. They are basically all engine. Those were some of the better memories of my young life.
The dealership is gone now. Shame. I wonder whatever happened to those 917s.
The "Aluminum Balloon" structure was actually pioneered by Wernher von Braun for the German V2 program, was later refined for the American space program through out the 50's and 60's and is still used in modern rocketry today.
Smooth transition into the ad, and a timer slider. If I weren't broke, I would buy that wallet. Good ads, good content.
1. Opposed engines are not narrower. 2. The nitrogen was to detect a broken frame due to it being so weak... shades of Colin Chapman.....and done AFTER creaks showed up after 1st race. Original version, before John Weir team got their hands on, was a death trap.