I knew pistons werent perfectly round all the way through their height these days, but didnt realise just how different the geometry is, very cool man :) always learning, and knowledge is POWER
You should have mentioned Honda's attempts at trying to make squarish oval pistons work in a desperate attempt to maximize bore area for a given sized block. That went well...
Looks like himself again, back in the days I'd watched him make poly mounts... Super smart dude, I've actually made my own mounts not long after you made your video. Keep on keeping on.
I'm sure you've thought about it, but I'd love a video on wrist pin height as well. Also, do any pistons have a pin offset from the center? Towards the major thrust side for example? Great vid as always!
That's a great topic suggestion! Thank you. There's definitely offset pins out there, many new engines have them. It reduces friction, reduces NVH too. I'll definitely cover it in the future.
do you know that the hole for the pin is usually not in the center but slightly offset (we're talking 1mm max) toward the exhaust? i don't remember why tho!
The pin is slightly offset, so when the full force hits the piston at Top Dead Center, the rod isn't standing straight on the crankshaft, but rather starting to go down, thus converting more force into rotary motion, rather than just smacking your crankshaft
Thank you for the Piston explanation I always thought it was a little simpler than that but apparently there's a lot of math in it, congratulations on your haircut signs of growing up There's Hope for you yet.....lol
It can be done on some engines, but on many engines the mains overlap the bore bottom or there's simply some sort of lip or something in the block. But even when you can remove them from the bottom there's no benefit to it, because you can't install them from the bottom.
Thanks for another great video. I have thought about the things you covered but have a hard time finding good sources of accurate information online. Do you have any books or other sources you would recommend that goes into depth on cylinder and piston geometries as well as the combustion chamber and valve configurations?
Very detailed and informative video. Could you please answer the question: why is it that the main bearing axis is symmetrical below the cylinder bore axis. Couldn't you counteract the main thrusts loadings on the pistons through a asymmetrical design or a flat mounted engine?
A piston is a very complicated object: not only like explained here, but the pin bore from the piston is not cylindrical : it as special forms (double cone like+ oval) , to compensate the flex from the pin and from the piston+ lubrication...and much more hidden secrets...(i had work by Mahle and Kolbenschmitt...)
Great content and superb video. A lot of engine builder rotate the piston in the bore because of the pin offset, what does this do to the major and minor thrust surfaces? And wear and tear?
Im an a apperentice engine builder by trade and dude I CANNOT GET ENOUGH OF YOUR CONTENT its super informative and intriguing and watch every video that you put up as soon as you do please keep up the amazing work so i can keep learning and to keep enjoying your videos
Your information is wrong in 2 strock there is no taper because petrol mix with oil circulate the rong .including piston in four strok piston taper i given after the piston ring taper well given in oil ring sronded by small holes because piston go down in cranshaft and go to T D C OIL WELL SUCK AND COMONG FROM THE OUTER DIA OF THE PISTON HOLES .THAT TAKES LUBRECATE THE PISTON AND LINER INCLUDING PISTON RING ,without taper piston well waroute withen few seconds this my practical experience you mindet
It also makes it harder to measure the piston to wall clearance accurately especially when the piston manufacturer doesn't provide a gauge point. Sure the piston alloy must also effect these geometries. Another show of the engineering marvel that is the 4 stroke ICE
haircut became boring like the grey mass of people & is just like in the military (but the beard does not fit to military unless its in Saudi-Arabia / Iran / ... )
0:35 is not the taper (a cone shape would have flat sides and not let light through). This effect is because of the "barrel" shape (barreling). This allows the piston to better handle the side loads from the connecting rod. Pistons are pushed sideways into the bore by the connecting rod, and the barrel shape helps with this so the top and bottom edges don't dig in.
I feel like Western English even though not the most efficient language, is able to convey the most acute, detailed and understandable level of communication between people trying to explain things to each other.
You are wrong about the reason for the shape it is narrower across that section because of thermal expansion, it expands more across that area because it has more mass under operating conditions the piston is infact round
Damn what I've done I've put a piston inside the engine cylinder without a piston ring, to check the bore, cause i dont i have a tools try to rotate it and got stuck all of four cylinder and i think the problem is a bore so i go to the machine 😞 Co'z i thought a piston is rounded
How long does it take that the Piston cools down while a brake with shout of engine and how long does it take to get again to perfect expansion when you start the engine again? Does a 15 min break with 1 minute time to warm up again before full load (on the highway for example) means a lot of stress for the piston and the cylinder bore?
Hi guy. Offset pistons can equalize major and minor thrust, reducing total friction while increasing power, efficiency, and torque. My guess is that they aren't universally used because offset pistons complicate balancing. And adding a thermal break while using the appropriate metal for each sub-part of a piston is far superior to the kluge that is currently standard in obsolete designs. This sort of design also simplifies each part, which makes forged parts practical, greatly improving all aspects of performance without breaking the bank. The above improvements make your engine wayyyy more efficient. They are also some of the several improvements by which a truly modern engine protects its oil from heat and blowby. Oil changes ought to be very, very infrequent. They are needed so often because of contamination and degradation, both of which are glaring indicators of poor design. All in all, a fun little video. Thanks and have a good one. :-)
If your solution weren't far more difficult than the current one, it would already be used. If you believe that to be untrue, start a piston company, and make the automotive world a better place! :)
I simply love learning the details of the basic parts of the engine and how complex they really are! Without you not sure I ever would learn these details.
Most measure it 90 degrees from the pin at a predetermined height from the bottom of the skirt. The height depends on the piston and manufacturer, but it's usually close to the bottom.
I'm a huge fan of your job but today I disagree with some explanations you give. I'm pretty sure that the barrel shape is done due the fluidynamics of the oil in the cylinder wall, in particular to have a meatus of olil and an oleohydraulic lift that keep the skirt apart from the cylinder wall and avoid metal to metal contact
That's pretty much what I said, I just didn't use the words "meatus" and "oleohydraulic". Friction reduction is basically what it's about. By the way, Google "meatus", I'm afraid it's a bit out of place here 😉
@@d4a I traslate italian meato in meatus, I agree with you that's not used in the same way I use it. I'm sorry. btw if you know it's a pity that you don't explain deeply like you have get used us. But don't worry man it's only a whim of mine
Haircut looks good.
Thank you 😊 I ran out of patience with the long version
Did you mean: I like ya cut G
@@natejohnson6269 Uhhmmm. Huh
Alonso accent: much better than before, amazing
Excellent cut my dude.
Nice
Why don’t we have dorito shaped pistons 🤔
Because braaaaaaaap
because it will *chip*
Bro, Rotary ?
some people just can't handle real power when they hear it...
We do its called a wankel :)
Once again, I learned. And yes, haircut looks good. ;)
Thanks my man!
I got a divine revelation!! My vision of piston will never be the same!!
I FORGOT FOR A SECOND! NICE HAIRCUT BRO YOU LOOK BEAUTIFUL!
I'm a beautiful short haired butterfly 🦋!
The only channel that deserves to share. Thank you so much . Your biggest fan from Saudi Arabia
I knew pistons werent perfectly round all the way through their height these days, but didnt realise just how different the geometry is, very cool man :) always learning, and knowledge is POWER
You should have mentioned Honda's attempts at trying to make squarish oval pistons work in a desperate attempt to maximize bore area for a given sized block. That went well...
what engine are you talking about ?
@@michalwilk4748 Honda NR Engine. They wanted to make it to pass the regulations.
Looking sharp with that hair cut!
Thanks man
That made pretty hard to develop Honda`s NR750 oval pistons.
The rings were also a big problem on those.
Looks like himself again, back in the days I'd watched him make poly mounts... Super smart dude, I've actually made my own mounts not long after you made your video. Keep on keeping on.
talks a lot more though ;)
I literally could not keep my eyes off the haircut. Looks good man👍🏻 great video as always
Unstable skirts have their good points
Looks like motorists got caught up in technical stuff 😂.
my dude i like the new hair style haha
Wow Man, you are looking handsome with that cool haircut
Thanks man!
I'm sure you've thought about it, but I'd love a video on wrist pin height as well. Also, do any pistons have a pin offset from the center? Towards the major thrust side for example? Great vid as always!
That's a great topic suggestion! Thank you. There's definitely offset pins out there, many new engines have them. It reduces friction, reduces NVH too. I'll definitely cover it in the future.
@@d4a are waiting
do you know that the hole for the pin is usually not in the center but slightly offset (we're talking 1mm max) toward the exhaust? i don't remember why tho!
The pin is slightly offset, so when the full force hits the piston at Top Dead Center, the rod isn't standing straight on the crankshaft, but rather starting to go down, thus converting more force into rotary motion, rather than just smacking your crankshaft
@@MinecraftNickTV Thank you!
@@MinecraftNickTV ...THAT'S an excellent explanation !! I couldn't get my head around before 👍
Thank you for the Piston explanation I always thought it was a little simpler than that but apparently there's a lot of math in it, congratulations on your haircut signs of growing up There's Hope for you yet.....lol
You may have convinced him to grow the hair out again! I enjoyed the piston explanation as well - more to it than I knew.
Been building engines for years and still learned a few things here. Great video.
So why can't you pull pistons through the bottom of a block
It can be done on some engines, but on many engines the mains overlap the bore bottom or there's simply some sort of lip or something in the block. But even when you can remove them from the bottom there's no benefit to it, because you can't install them from the bottom.
The whole explanation isn't valid without a reason for the new haircut 😄👌.
The only place that my pistons stay outside the engine are in bubble wrap or an oil bath
Congrats?
Great video. What is this guy’s background? Degree?
Thnx
Thanks for another great video. I have thought about the things you covered but have a hard time finding good sources of accurate information online. Do you have any books or other sources you would recommend that goes into depth on cylinder and piston geometries as well as the combustion chamber and valve configurations?
The man teaching me what i didn't get to learn in tech school
Never knew this one! Very interesting!
I love your content please keep it up!!!!
you are good at what you do!
I like ya cut g
Very detailed and informative video. Could you please answer the question: why is it that the main bearing axis is symmetrical below the cylinder bore axis. Couldn't you counteract the main thrusts loadings on the pistons through a asymmetrical design or a flat mounted engine?
Why don't we have oval VALVES?
This was a fun video, on a Sunday morning enjoying breakfast.
A piston is a very complicated object: not only like explained here, but the pin bore from the piston is not cylindrical : it as special forms (double cone like+ oval) , to compensate the flex from the pin and from the piston+ lubrication...and much more hidden secrets...(i had work by Mahle and Kolbenschmitt...)
So how to make perfect piston
thank you great video happy new hair cut
Did'nt go into off set wrist pin locations?
Thanks for the great explanation
Great content and superb video. A lot of engine builder rotate the piston in the bore because of the pin offset, what does this do to the major and minor thrust surfaces? And wear and tear?
Thank you so much once again bro
New haircut. Looks great and as allways great video ☺️
Thank you 😊
Awesome haircut!
Im an a apperentice engine builder by trade and dude I CANNOT GET ENOUGH OF YOUR CONTENT its super informative and intriguing and watch every video that you put up as soon as you do please keep up the amazing work so i can keep learning and to keep enjoying your videos
Thank you for this amazing comment
And also please send me a link to your merch page as I'm struggling to find it and would like to buy a couple of pieces of merch thx
It's always at the bottom of the description 😊
ohhhh where are the hair bro? haha
Your information is wrong in 2 strock there is no taper because petrol mix with oil circulate the rong .including piston in four strok piston taper i given after the piston ring taper well given in oil ring sronded by small holes because piston go down in cranshaft and go to T D C OIL WELL SUCK AND COMONG FROM THE OUTER DIA OF THE PISTON HOLES .THAT TAKES LUBRECATE THE PISTON AND LINER INCLUDING PISTON RING ,without taper piston well waroute withen few seconds this my practical experience you mindet
It also makes it harder to measure the piston to wall clearance accurately especially when the piston manufacturer doesn't provide a gauge point. Sure the piston alloy must also effect these geometries. Another show of the engineering marvel that is the 4 stroke ICE
I like ya cut, G!
Cool, thank you!!!
Awesome content, thank you! great channel, hope you get more subscribers and supporters!
I’m digging the new hairstyle. Also, another awesome video. Cheers!
Really good stuff man! Dropping a comment to help out the algorithm.
Nice haircut there
Another great video! Thank you very much!!
great stuff
haircut became boring like the grey mass of people & is just like in the military (but the beard does not fit to military unless its in Saudi-Arabia / Iran / ... )
ive learned this at school but never seen it like this good hair style dude
0:35 is not the taper (a cone shape would have flat sides and not let light through). This effect is because of the "barrel" shape (barreling). This allows the piston to better handle the side loads from the connecting rod. Pistons are pushed sideways into the bore by the connecting rod, and the barrel shape helps with this so the top and bottom edges don't dig in.
I feel like Western English even though not the most efficient language, is able to convey the most acute, detailed and understandable level of communication between people trying to explain things to each other.
Huh, never knew that! Thanks for the clear and concise reasoning my dude!
Thank you!
Hair looks good, but I thought the long hair was cool too!
You are wrong about the reason for the shape it is narrower across that section because of thermal expansion, it expands more across that area because it has more mass under operating conditions the piston is infact round
Hey buddy, I am following you long time. I have a few questions for my car... I will ask on IG
Damn what I've done I've put a piston inside the engine cylinder without a piston ring, to check the bore, cause i dont i have a tools try to rotate it and got stuck all of four cylinder and i think the problem is a bore so i go to the machine 😞
Co'z i thought a piston is rounded
How long does it take that the Piston cools down while a brake with shout of engine and how long does it take to get again to perfect expansion when you start the engine again? Does a 15 min break with 1 minute time to warm up again before full load (on the highway for example) means a lot of stress for the piston and the cylinder bore?
the fact that every time i have an engine question which you answer in a video is astonishing
missed the oval of the crown to correct for the exhaust side thermally expanding more.
logic is off. The mass is concentrated in the crown, and the diameter at the crown is smaller diameter.
what an explanation! you just got a subscriber here.
Let us know this whole debate on turning pistons 180 degrees for more power
What does it meany by skirt? I don't understand what skirt is
You look so different with short hair :)
lol, i can't believe how good it ran with the pistons in backward.
Gr8 material mate, thank You!
also the pin hole isnt on the y axis. it has a offset
U look refreshed!!!
Thanks 😊
Hi guy. Offset pistons can equalize major and minor thrust, reducing total friction while increasing power, efficiency, and torque. My guess is that they aren't universally used because offset pistons complicate balancing.
And adding a thermal break while using the appropriate metal for each sub-part of a piston is far superior to the kluge that is currently standard in obsolete designs. This sort of design also simplifies each part, which makes forged parts practical, greatly improving all aspects of performance without breaking the bank.
The above improvements make your engine wayyyy more efficient. They are also some of the several improvements by which a truly modern engine protects its oil from heat and blowby. Oil changes ought to be very, very infrequent. They are needed so often because of contamination and degradation, both of which are glaring indicators of poor design.
All in all, a fun little video. Thanks and have a good one. :-)
If your solution weren't far more difficult than the current one, it would already be used. If you believe that to be untrue, start a piston company, and make the automotive world a better place! :)
Ovaltine with milk Yummy!🥛
What kind of piston is that @ 5.10?
Thank you, fascinating.
Finally....man bun free!!!
do pistons change shape as they get hot?
Did it hurt? Getting your hair cut?
Good time to explain piston slap.
Pistons are not round because they don't expand evenly. 'Cam Ground' was the term used in the past, because of this characteristic.
Do you have any good engineering source where to calculate piston dimensions like bore, height, taper, ovality, etc.? Would love to get any lead
I was expecting a few words on piston pin offset, but it would have gone beyond topic I suppose.
Brilliant as usual :)
Hair is looking great dude, couldnt stand the maintenance anymore? :P i feel that haha
Definitely, ran out of patience 😅
Did not know that pistons had a side
Very informative and useful video. Thank you very much!
Very cool video. Is there also a video about the zylinder, the bore and the hone coming??
Pure dry learning material without water. Super! Thank you!
Nice video and keep it up.
I simply love learning the details of the basic parts of the engine and how complex they really are! Without you not sure I ever would learn these details.
Piston porn.. love it
Is 4 stroke taper and ovality same as 2 stroke engine pistons?
So is it possible to install a piston the wrong away around?
Yes, but most have markings on top that tell you which way it needs to be directed.
Looking good my man! I like what you did with your hair!
Haircut shock
So where does the piston measure its nominal size?
Most measure it 90 degrees from the pin at a predetermined height from the bottom of the skirt. The height depends on the piston and manufacturer, but it's usually close to the bottom.
I'm a huge fan of your job but today I disagree with some explanations you give. I'm pretty sure that the barrel shape is done due the fluidynamics of the oil in the cylinder wall, in particular to have a meatus of olil and an oleohydraulic lift that keep the skirt apart from the cylinder wall and avoid metal to metal contact
That's pretty much what I said, I just didn't use the words "meatus" and "oleohydraulic". Friction reduction is basically what it's about. By the way, Google "meatus", I'm afraid it's a bit out of place here 😉
@@d4a I traslate italian meato in meatus, I agree with you that's not used in the same way I use it. I'm sorry.
btw if you know it's a pity that you don't explain deeply like you have get used us. But don't worry man it's only a whim of mine