I’d advise a fillet or chamfer on the inside corner, what you did created a sharp inner corner which will cause unneeded stress on the part and be more likely to grenade your engine. Also, you should have protected the inside of the rod to not mess up your bearings.
This was done for performance, race applications. No radius in the corner of the cut introduced a fracture point for the bearing cap to fail. Honda caps are already weak when it comes to Twisting the screws to them lol.
Thank you for making this video. Quick question does this take the strength away from the rod or in some cases can this actually strengthen it because you're potentially taking the rough part of the material away and turning it into a machined part? I realize there's probably a very fine line in between taking too much and weakening it or taking from the right areas and strengthening it.
WOW lots of expert machinists in the UA-cam comments section. Lol. I'm a huge fan of machining down excess weight for race applications. I'd love to bring my Forged Ford modular crank with rotating assembly down to trim some fat off the whole piston, rod, crank assembly. I'll be calling you guys up to schedule it soon.
Will need to heat treat/stress relieve the rod after messing with its surface. The goal is to harden the surface without going too deep and making the rod brittle. Shot peening the surface of the rod can relieve stress while work hardening the outer layer of metal. Various micro-polishing treatments can also enhance a rod’s durability while leaving a great-looking finish that sheds oil.
You could loosen up some more power by removing more weight and friction at the cost of more crankpin pressure by removing that slight collar on the sides of that rod right?
Im kind of confused, you want to lighten the crank assembly to gain more torque at higher rpms, while it is weaker at higher rpms. I think this is better to use to make al the rods te exact same weight to gain less vibration.
8500 rpm, not worried in the slightest. The crank now thinks its heaver by 160 grams, a good thing for higher rpm's. I add weight to some cranks so that they will survive extended high rpm's, no big secret here dude.
I have a set of dsm eagle rods and the bushing on top are ID 21mm and I would like to know if you could swap them for 22mm ID for the 2g pistons and weight match all rods?
I've built very serious Turbo charged BMC Cooper 'S' motors moving them from 85bhp to over 200BHP at the wheels. For those who say that these mods make the engine unreliable are inexperienced. Lightening the internal rotating mass as a parabolic effect on acceleration. However, its also reduces torque. or stored internal mass. If you re after all out power and aren't concerned with torque then these mods are number one..once these rods are shot peened they will be fine for 8,000RPM plus and get you there quicker!
You must be inexperienced with Honda's. These rods aren't every strong as it is. It is WELL documented that these rods fail around 220-250 hp. If you want to lighten rotational mass it would be better to lighten the flywheel and valvetrain as well as balancing the complete rotating assembly. Even if you shit peen and cryogenicly test then they are still weaker than if you would have never shaved them and effected the integrity of the rods.
I see no logical reason to do this modification .What about oil control , rod side float, and bearing to fillet clearance?You want less mass machine the crank and install a lightweight flywheel.
Dillon West just buy the Honda Civic GX pistons they are 12.5 compression pistons that are forged. They come out of a d16 that runs propane. If you don't want high compression shave the dome of piston down at machine shop. Then you have a factory forged piston that fits the LS rod
I spun a rod bearing, I know 3 of my con rods may be messed up, what can I do after this had happened? The engine is a GM 3800 supercharged V6, I don't want to upgrade my motor, just want to get it running again. I would buy a new crankshaft and bearings, just wanted to know what I can do about the rods.
Really like your attention to detail, but live nowhere close to you. Would you know of a good machine shop near me (95076 - Monterey Bay)? I'dlove to gat some lightening done on my Corvair engine parts, as well as a quality crank/rotating assembly balancing. Hope to hear back.
I gave you guys a call but didn't get anyone...is this service on these rods still a thing? Do you think that doing this will help increase gas mileage any? I'm out to build an ecomodder d16y8 engine...and lightening components have become my #1 priority. If so, how much would a set of rods run me if I sent them your way?
Jared, we don't answer the phone much any more because we are so busy. Would suggest that you send/bring the rods by for service. John... BTW, this it the new fiatnutz channel.
Just get aluminum rods if your worried about weight. There is no good reason to do this. Get some aluminum rods and balance them yourself. It’s easy enough! Cheaper in the long run too.
+Nick Christiansen It's not a performance engine though. If they are willing to reduce reliability, of this admittedly cheap engine where they cheaply get another junkyard one, then it's ok.
Does anybody know if there is a video where he's balancing this conrods with a crankshaft? Or a video of the engine with this conrods? This doesn't seems logical but maybe he has a reason.
Thomas Miet there are, just not for this Honda setup. check his video library, I believe there are Toyota rods being balanced, and another one with a Subaru crank being balanced.
It has been three years but dead guys cant defend themselves. This guy isnt doing his first round and yall aught to just be quiet and think about how it works and what the advantages and disadvantages are. cutting rods is a common practice because less mass = less intertia which is a good thing. I want to take 40G off my rods and damn I wish I could call him.... BTW what I was getting at is some classes require a stock p/n and lighter rods give you the response.
Just found this but has this guy passed on? If so it is a shame. This guy was on the ragged edge sometimes but always seemed to know what he could get away with and be safe. Guess that is why they called it R and D.
Tommy TheNice Looking at the thickness of the material at the connecting rod I-beam and the small end, that is definitely NOT aluminium. It’s more than likely cast or forged steel if stock Honda parts.
Hard jaws on a soft, critically dimensioned ID. Nice. Copper shims won't even help because not only is marring an issue but I'll bet you can't get 0 at every degree in that ID. Those jaws distort it shes out of round now no?
Now your rod side clearance is what? >.2 inches. Does the bearing still fit? And is the fillet now going to rub on the bearing? What about rod side float which could cause havoc if the piston clearance is large. Very questionable modification with really no measurable hp increase. Tell us what your logic is?
If you take that rod with the mods he did and do an FEA (Finite Element Analysis) you would see why people are negative. If your intent is to run this for 100 laps and toss it in the scrap bin, it may survive. I wouldn't suggest it for anything that is going to see a lot of miles though.
Detonation, there are all manner of secondary motions in the reciprocating parts of an internal combustion engine. When the cylinder fires, the piston bends, the pin bends, the rod bends and the crank bends. May not be huge amount (can be), but the number of times it bends is just as harmful as the amount as it leads to fatigue cracking. The fellow doing this work introduced crack-prone areas with the small radius of the tool and by removing the gusset at the bolts and introducing a sharp corner where the gusset used to meet the bolt flat which is often a high load / stress area of the rod. Those gussets weren't put there to look pretty, they had a required purpose or that material would have been removed in the design stage of the engine. Might just be a few grams, but that is performance and cost (say 12 grams of steel over say 6 million 4 cylinder engines is 635,000 lbs of extra steel that has to be bought)
They aren't 'weaker'. Rods NEVER break there (they usually break at the stem)...it's non-integral to the actual stress exerted upon the rod. 40grams x 4 rods...takes a lot of effort to spin up and takes a long time to come back down. This is a good budget way to build, especially for circuit racers (rev-matching is easier with a lighter rotating assembly). Take a look at the real racing rods (like Carrillo), and notice the similarities. Power comes from many places...not just the 'head', but that is a whole book to write, not a youtube reply. ;)
Are you just talking out of your ass or are you actually serious? If lighter rods didnt make power than all the top 4 second dragsters running nitro methane wouldnt run billet aluminum rods. Oh whats that? Going with aluminum rods doesnt make horsepower? Any reduction in reciprocating mass makes power. Any engine not just Hondas that can rev up to 9,000 rpm and make power that high will suffer frictional horsepower losses with just a drop of oil on the rods, although small, it makes a difference. This is why there is dry sump oil systems. You just made yourself sound like an idiot by saying that lightening conn rods doesnt make power but lightening the flywheel does. It is all chunks of metal spinning at very high rpms, any reduction in weight and especially when blueprinted makes power. You are a keyboard racer talking shit while John actually gets out and races fiats. Go join your socialist obama lover group where "raising the debt limit doesnt raise the debt"....what a nerd.
I’d advise a fillet or chamfer on the inside corner, what you did created a sharp inner corner which will cause unneeded stress on the part and be more likely to grenade your engine. Also, you should have protected the inside of the rod to not mess up your bearings.
im guessing its naturally aspirated. i built a turbo d16 with the stock rods years ago. then a connecting rod exploded. good times
This was done for performance, race applications. No radius in the corner of the cut introduced a fracture point for the bearing cap to fail. Honda caps are already weak when it comes to Twisting the screws to them lol.
to be honest you should of put some used bearings inside the rod before mounting it to the lathe, or at least use a soft jaw chuck.
Thanks for the reply. I don't understand how adding weight to a crank is a good thing, though, unless it helps dampen the vibrations.
Thank you for making this video. Quick question does this take the strength away from the rod or in some cases can this actually strengthen it because you're potentially taking the rough part of the material away and turning it into a machined part? I realize there's probably a very fine line in between taking too much and weakening it or taking from the right areas and strengthening it.
WOW lots of expert machinists in the UA-cam comments section. Lol. I'm a huge fan of machining down excess weight for race applications. I'd love to bring my Forged Ford modular crank with rotating assembly down to trim some fat off the whole piston, rod, crank assembly. I'll be calling you guys up to schedule it soon.
Will need to heat treat/stress relieve the rod after messing with its surface.
The goal is to harden the surface without going too deep and making the rod brittle. Shot peening the surface of the rod can relieve stress while work hardening the outer layer of metal.
Various micro-polishing treatments can also enhance a rod’s durability while leaving a great-looking finish that sheds oil.
You could loosen up some more power by removing more weight and friction at the cost of more crankpin pressure by removing that slight collar on the sides of that rod right?
Nice video, but is it better to use a round bit to give a rounded finish instead of sqaured to prevent tensions?
yes, this will weaken the crank bearing connection and make the load less even. just don't rev it up too high. not for boosted engines
Im kind of confused, you want to lighten the crank assembly to gain more torque at higher rpms, while it is weaker at higher rpms. I think this is better to use to make al the rods te exact same weight to gain less vibration.
It's not a bit.
I'd be scared to take advice from someone who thinks 421.4 grams minus 369.9 grams equals 40 grams.
Or the fact he basically cut in a “sharp” edge (likely to cause cracks)
That poor Bridgeport with a round out bed...i hope you swing alot of rod's John!
8500 rpm, not worried in the slightest. The crank now thinks its heaver by 160 grams, a good thing for higher rpm's. I add weight to some cranks so that they will survive extended high rpm's, no big secret here dude.
How high will this engine be revving and are you concerned about taking that much off the big end of the rod for durability?
Curious the size of the lathe swing pre way knotching? Want to get an idea what size lathe I can get away with not needing the modification
I don't know much about machining engine parts. Why would someone want to lighten their connecting rods? Thanks!
I have a set of dsm eagle rods and the bushing on top are ID 21mm and I would like to know if you could swap them for 22mm ID for the 2g pistons and weight match all rods?
How about webbing the rod with lightening holes?
I've built very serious Turbo charged BMC Cooper 'S' motors moving them from 85bhp to over 200BHP at the wheels. For those who say that these mods make the engine unreliable are inexperienced. Lightening the internal rotating mass as a parabolic effect on acceleration. However, its also reduces torque. or stored internal mass. If you re after all out power and aren't concerned with torque then these mods are number one..once these rods are shot peened they will be fine for 8,000RPM plus and get you there quicker!
I have to admit, I would be scared removing that much material, but I guess he knows what he's doing. lol
You must be inexperienced with Honda's. These rods aren't every strong as it is. It is WELL documented that these rods fail around 220-250 hp. If you want to lighten rotational mass it would be better to lighten the flywheel and valvetrain as well as balancing the complete rotating assembly. Even if you shit peen and cryogenicly test then they are still weaker than if you would have never shaved them and effected the integrity of the rods.
I see no logical reason to do this modification .What about oil control , rod side float, and bearing to fillet clearance?You want less mass machine the crank and install a lightweight flywheel.
hands up..... if you were just waiting for the conrod to fly out and smack him in the face-----
Hello, im curious if you are able to machine and press a wrist pin bushing in to convert a 21mm wrist pin down to use a 19mm pin?
Dillon West just buy the Honda Civic GX pistons they are 12.5 compression pistons that are forged. They come out of a d16 that runs propane. If you don't want high compression shave the dome of piston down at machine shop. Then you have a factory forged piston that fits the LS rod
How much will this cost for four d16 rods
That's funny, Im sure Johns been at that lathe a million times and never seen that.
I spun a rod bearing, I know 3 of my con rods may be messed up, what can I do after this had happened? The engine is a GM 3800 supercharged V6, I don't want to upgrade my motor, just want to get it running again. I would buy a new crankshaft and bearings, just wanted to know what I can do about the rods.
cw2lido replace them,
Really like your attention to detail, but live nowhere close to you. Would you know of a good machine shop near me (95076 - Monterey Bay)? I'dlove to gat some lightening done on my Corvair engine parts, as well as a quality crank/rotating assembly balancing. Hope to hear back.
Wow, original weight 420g... half the weight of the MG connecting rods in the previous video! Both "low-output" engines.
I would but I have no clue who can do them here in Georgia.
I gave you guys a call but didn't get anyone...is this service on these rods still a thing? Do you think that doing this will help increase gas mileage any? I'm out to build an ecomodder d16y8 engine...and lightening components have become my #1 priority. If so, how much would a set of rods run me if I sent them your way?
Jared, we don't answer the phone much any more because we are so busy. Would suggest that you send/bring the rods by for service. John... BTW, this it the new fiatnutz channel.
VTEC kicked in!!!!
It will depend on how much wall the bushing has, no problem to equalize rod weights.
These rods were plus/minus 1,5 grams after I finished.
Did you grind your own ways to accommodate the rod?
good job
Just get aluminum rods if your worried about weight. There is no good reason to do this. Get some aluminum rods and balance them yourself. It’s easy enough! Cheaper in the long run too.
10/10 should not let near a lathe again (Y)
Quicker acceleration of the crankshaft.
Right untill that rod brakes
Compression Ignition Army people snap them all motor in autocross
Have them rebuilt and reuse them.
There's a perfectly good reason why the con rods weren't fifty grams lighter to begin with. Come one people!
+Nick Christiansen It's not a performance engine though. If they are willing to reduce reliability, of this admittedly cheap engine where they cheaply get another junkyard one, then it's ok.
The yellow label to the left of the chuck says "acroos" instead of "across" :-D
Does anybody know if there is a video where he's balancing this conrods with a crankshaft? Or a video of the engine with this conrods?
This doesn't seems logical but maybe he has a reason.
Thomas Miet there are, just not for this Honda setup. check his video library, I believe there are Toyota rods being balanced, and another one with a Subaru crank being balanced.
Rip John
Röhm-Chuck? Geeez.. We Germans made it to Costa Mesa at least :)
It has been three years but dead guys cant defend themselves. This guy isnt doing his first round and yall aught to just be quiet and think about how it works and what the advantages and disadvantages are. cutting rods is a common practice because less mass = less intertia which is a good thing. I want to take 40G off my rods and damn I wish I could call him.... BTW what I was getting at is some classes require a stock p/n and lighter rods give you the response.
Just found this but has this guy passed on? If so it is a shame. This guy was on the ragged edge sometimes but always seemed to know what he could get away with and be safe. Guess that is why they called it R and D.
So he was holding an alluminum rod with hardened steel jaws on the mating surface with no shims whatsoever? Heeell nooo to the nononoooo
Tommy TheNice Looking at the thickness of the material at the connecting rod I-beam and the small end, that is definitely NOT aluminium. It’s more than likely cast or forged steel if stock Honda parts.
Forged steel
Hard jaws on a soft, critically dimensioned ID. Nice. Copper shims won't even help because not only is marring an issue but I'll bet you can't get 0 at every degree in that ID. Those jaws distort it shes out of round now no?
how to successfully weaken already weak honda rods -__-
+Mo Baklava although this guy is just making a living and doing as the amazing Honda customers requested
Now your rod side clearance is what? >.2 inches. Does the bearing still fit? And is the fillet now going to rub on the bearing? What about rod side float which could cause havoc if the piston clearance is large. Very questionable modification with really no measurable hp increase. Tell us what your logic is?
he doesn't remove material on the bearing face look what he's doing and where he is taking off material man cmon. aka the side clearance is THE SAME.
Stupid
Put'em in a box and send them to the shop.
Costa Mesa R&D Automotive Machine Shop
123 Monte Vista Avenue
Costa Mesa, CA 92627
werent light enough..? heh 1 alfa romeo rod wieghts 4 of yr honda
per fare un bel avoro ci vogliono le griffe tornite non quelle in acciaio con gli spigli😭😭😭
ground*
Perhaps it's a Canadian machine.
Not gonna lie....i'm here just for the fuckups
"werent light enough..? heh 1 alfa romeo rod wieghts 4 of yr honda" What engine? Alfa V6 or I4? :)
Lets see... just for snorts & giggles (where's that calculator), 421.4g to 369.9g comes to a ∆% of -12.22!
Hii
why is everyone so negative?
If you take that rod with the mods he did and do an FEA (Finite Element Analysis) you would see why people are negative. If your intent is to run this for 100 laps and toss it in the scrap bin, it may survive. I wouldn't suggest it for anything that is going to see a lot of miles though.
Detonation, there are all manner of secondary motions in the reciprocating parts of an internal combustion engine. When the cylinder fires, the piston bends, the pin bends, the rod bends and the crank bends. May not be huge amount (can be), but the number of times it bends is just as harmful as the amount as it leads to fatigue cracking. The fellow doing this work introduced crack-prone areas with the small radius of the tool and by removing the gusset at the bolts and introducing a sharp corner where the gusset used to meet the bolt flat which is often a high load / stress area of the rod. Those gussets weren't put there to look pretty, they had a required purpose or that material would have been removed in the design stage of the engine. Might just be a few grams, but that is performance and cost (say 12 grams of steel over say 6 million 4 cylinder engines is 635,000 lbs of extra steel that has to be bought)
Take weight from pin side, because it belongs up and down movements. That is almost waste of time...
you know youre a ricer when...
john martin you do this🤣
Jackess...
Congrats, you just weakened your rod. There's no power gain from conrod modifying, the power comes from engine head.
They aren't 'weaker'. Rods NEVER break there (they usually break at the stem)...it's non-integral to the actual stress exerted upon the rod. 40grams x 4 rods...takes a lot of effort to spin up and takes a long time to come back down. This is a good budget way to build, especially for circuit racers (rev-matching is easier with a lighter rotating assembly).
Take a look at the real racing rods (like Carrillo), and notice the similarities.
Power comes from many places...not just the 'head', but that is a whole book to write, not a youtube reply. ;)
There's a lot easier place to save rotating mass: flywheel.
#1 place is flywheel,clutch and pulleys for sure.
Can you provide some evidence to show that this specific modification has resulted in con rod failure? If so where is the evidence?
Are you just talking out of your ass or are you actually serious?
If lighter rods didnt make power than all the top 4 second dragsters running nitro methane wouldnt run billet aluminum rods. Oh whats that? Going with aluminum rods doesnt make horsepower?
Any reduction in reciprocating mass makes power. Any engine not just Hondas that can rev up to 9,000 rpm and make power that high will suffer frictional horsepower losses with just a drop of oil on the rods, although small, it makes a difference. This is why there is dry sump oil systems.
You just made yourself sound like an idiot by saying that lightening conn rods doesnt make power but lightening the flywheel does.
It is all chunks of metal spinning at very high rpms, any reduction in weight and especially when blueprinted makes power.
You are a keyboard racer talking shit while John actually gets out and races fiats. Go join your socialist obama lover group where "raising the debt limit doesnt raise the debt"....what a nerd.