H22 piston talk.

[Gettin_faster91]

I have some questions about the h22 pistons and what they are made of. For starters were all told not to run after market forged pistons in the h22 due to the frm sleeves. Ok fine but why? What are the oem pistons made of that make them special and able to work with the h? Fact is the piston don't touch the sleeves anyways or do they? I know the piston skirts can and will due to the pivot movement of the piston as its moves up and down. The rings must be special too seeing they are in contact with the sleeves all the time, other than the thin film of oil that lubricate them. I know there are coated and or mahl? sp pistons now available. But whats myth and whats fact. Is this just a ploy to get people to get iron sleeves installed? so with that said here are my questions.

1. Are the h22 pistons and rings made of a special metal to work with the frm sleeves.
2. If the answer to question one is yes why the hell don't they make a better piston with updated ring land's to handle better boost using the same materials.
Understanding that the frm sleeves are weaker is the case of boost/ high no2 shots i can understand getting iron sleeves for this. But again whats fact from fiction here guys. Why cant the pistons and forged sleeves get along?

Thanks in advance.

[Gettin_faster91]

Bump for knowledge.

[Vtechno]

http://hondaswap.com/engine-building...leaving-14101/

[desol11]

the h22 and h23 have the same frm sleeve, so does the nsx and a couple of other highend cars. and i know from first hand expierence that its not a myth running forge pistons on frm = kaboom, and thats because the forge pistons when they get hot they expand on that frm it really scars them up. ive seen it firsthand. as far as the sleeve being week thats a myth they are very strong, if u get the mahle pistons there the only one i know of that make pistons where u dont have to sleeve the block. u wanted to know why more aftermarket companies dont produce similar pistons, because douch bag wont support them if there is a demand then they will make them. mahle put there out some 3 years ago and i was one of the first people to buy them they been working fine ever since. i say instead of sleeveing a close deck block i say get the mahle coated turbo n2o pistons and call it a day and there pretty cheap they run only like 400 bucks. i hope that helped ya

[Vtechno]

the mahle pistons were in Honda Tuning a few months ago, and it pretty accurately described why you cant use most forged pistons. find a friend who read its religously and flip through.

OR

call Mahle. im sure one of the reps can describe it.

[Gettin_faster91]

Ok so what i was reading is telling me that it's the expansion of the forged pistons that are the cause of the problem. Meaning the two metals piston/ sleeves are expanding at different rates. And the stock pistons are iron in the h22. So it makes scenes to me that the forged aluminum pistons expands at a greater rate than the sleeves causing contact. Can they not used forged iron? (for high boost) and just make better pistons as far as the ring lands go out of iron for up to 10-15 psi of boost. Make them like they do with clutches stage one(stock) stage two (redesigned ring lands iron) to handle higher than average boost. And a race stage (forged aluminum that you need the iron sleeves)! God if only life was so simple lol

[jDmacCordh22a]

the stock pistons are cast aluminum, nothing really special or diff. as far as stock honda pistons are concerned but the rate of expansion and the strength of the metals is what makes the difference, forged pistons are not as soft as the cast alum pistons.

[rudy1980]

go to the link in #3 and then read that and then follow the link there everything is explained.

For those who don't want to take the extra steps:
In short the cyclinders are aluminum with a .5mm coating (frm), you can use forged pistons of the SAME bore as stock or up to .25mm larger you can only bore the stock cyclinders .25mm, anything else you have to sleeve the block. So if you can get high comp. piston in stock size your fine, same for low comp. pistons.

[koolkoreanked]

Ok so what i was reading is telling me that it's the expansion of the forged pistons that are the cause of the problem. Meaning the two metals piston/ sleeves are expanding at different rates. And the stock pistons are iron in the h22. So it makes scenes to me that the forged aluminum pistons expands at a greater rate than the sleeves causing contact. Can they not used forged iron? (for high boost) and just make better pistons as far as the ring lands go out of iron for up to 10-15 psi of boost. Make them like they do with clutches stage one(stock) stage two (redesigned ring lands iron) to handle higher than average boost. And a race stage (forged aluminum that you need the iron sleeves)! God if only life was so simple lol

lol there isn't a boost level as to where the stock ring lands break on a h22. Because 15 lbs of boost out of a vw/audi/porsche k03 is not the same as 15 lbs out of gt35r. In other words my buddy ran a turbo h22 with a crappy t3/t4 50 trim at 15lbs of boost on the stock motor. Mostly untuned. It ran so rich it looked like a diesel truck at the staging area at the track. It ran a 11.9 second run out at the track. He eventually blew the piston rings out from a 5 gear pull beating a 600cc bike. Mahle pistons are your friend. Thats what I'm going to run on my new h22 project.