pistons

[maney77]

hey guys an girls.. I wanna install a high compression pistons without the boring an things of that nature. i know the f22's come with a 8:8:1. wanted to see what companies out there offer a highier ratio, like a 9:6 or 10:5. so if anybody know of anything just hit me up...

[cloudasc]

Arias, Bisimoto, and Wiseco comes to mind.

[HondaFan81]

Wiseco have off-shelf higher CR pistons with stock 85mm bore. I know www.raceeng.com is one source, do research for others to compare pricing.

[wed3k]

I was about to post a thread regarding a 85mm piston but with higher compression.

a .040 oversize B20 piston is 85mm and i know RS machine offers a high compression cast piston and it will cost less than 200 bucks.

the only complication is that the wrist pin is different. they run a .827 as opposed to the .866 like f22's.

Now if you can hone the piston bore out .040, will it lose its integrity? I really want to try this because i have a f22 with only 30k miles and the bores are hardly even worn (which reminds me, i have it sitting outside uncovered and the walls are starting to rust)

[dbsharp]

I was about to post a thread regarding a 85mm piston but with higher compression.

a .040 oversize B20 piston is 85mm and i know RS machine offers a high compression cast piston and it will cost less than 200 bucks.

the only complication is that the wrist pin is different. they run a .827 as opposed to the .866 like f22's.

Now if you can hone the piston bore out .040, will it lose its integrity? I really want to try this because i have a f22 with only 30k miles and the bores are hardly even worn (which reminds me, i have it sitting outside uncovered and the walls are starting to rust)

hum Ive been thinking...
stock press fit rods, and a b20 pistion with the hole board out to the right size. Sounds like an economical solution to making moderate amounts of horsepower reliably... I have boost in mind for this combo. I am going to do some sort of build in the next 6 months, and I just don't think Ill have the cash to get f22a forged pistons and rods. The cheapest pistons Ive found are around $450 and you can get some 4340 rods for around 250 on ebay or grab some from bisi for 320.

*Edit* A friend of mine got some of these pistons cheep, but it looks like they are just as expensive as anything else normaly.

[d112crzy]

Why not just get the rod end rebushed to match the pistons bore?

[wed3k]

f22 rods are a press fit, not floating. aiming to use stock rods.

if youa re going boost, you might want to just go with a forged assembly. it's a little more full proof. and this idea was more for a cheap high compression engine. probably with stand 200hp.

[d112crzy]

You can still rebush a stock, press fit rod.

[wed3k]

You can still rebush a stock, press fit rod.

meh, ill ask about it tomorrow. you'd have to get custom bushings made because i know that all the bushings ive done are usually only .010 over size. so id have to get .025 oversize.

however using the smaller wrist pin will lighten up the assembly which is always a plus.

I originally wanted to use a K20 piston but i didnt feel like going 86mm.

[wed3k]

here's the D/l.

you can rebush them but it will have to be a custom bushing for sure. if you can find a bushing insert that is off the bat .040 or over thick but will fit in a .866 hole then it will be perfect that way you wont have to bore the rod to fit a bushing.

If you bore the hole, you weaken the material.

Honing the piston is still doable but taking .040 out of the piston will take a LONG time. It takes me half a day just to do a full set of rods on a v8. you also have to worry about the length of the wrist pin, i dont know if the castings in the pistons differ for length.

another thing is that the dealer on honda market for RS machine flaked. so trying to get a cast B20b high compression piston that is .040 (85mm) may be close to impossible. the only other thing is to tap into other people's old stock of RS pistons.

[dbsharp]

I have a set of forged 85mm b16 pistons that would yield between 9-10:1 compression depending on which head I use and the actual lenght of the rod I use.

I am going to attempt to use these in my super low budget turbo build. my question is: do the stock rods have bushings in them or is the .866 hole just machined into the steel?

Is there any reason that I could not use the floating wrist pin press fit into the rod?

I have sent bisi and cat emails about getting a f22a rod made with the smaller 21mm ID bushing. maybe I can get a forged rod made to fit. The other option is for me to buy a 4340 rod and press the bushing out, draw a design up for a new bushing and try to get it machined.

[wed3k]

I have a set of forged 85mm b16 pistons that would yield between 9-10:1 compression depending on which head I use and the actual lenght of the rod I use.

I am going to attempt to use these in my super low budget turbo build. my question is: do the stock rods have bushings in them or is the .866 hole just machined into the steel?

Is there any reason that I could not use the floating wrist pin press fit into the rod?

I have sent bisi and cat emails about getting a f22a rod made with the smaller 21mm ID bushing. maybe I can get a forged rod made to fit. The other option is for me to buy a 4340 rod and press the bushing out, draw a design up for a new bushing and try to get it machined.

well, the wrist pin woul dhave to be a .866 and you would just hone the rod out a couple tenths or thou (since they are a press fit)

stock rods have no bushings.

a h22a4 uses a bushing, im wondering what sizes they can offer.

[dbsharp]

I am thinking that a stock rod with a a custom steel bushing that has a FN2 fit (about .001" interference) between the rod and bushing, and wrist pin and bushing would allow me to use these pistons with stock rods. I wouldn't use the c clips that came with the piston, I would just press the wrist pins in there.

Opinions?

[wed3k]

well, you can still heat the rod and just slide the pin in when it is cherry red. the end will grow more than .002

[dbsharp]

yea but it still requires a bushing of some sort.