The motor is a 92 JDM H22 with chipped pistons and a friend found some 98 USDM Type S pistons, will they work? I know the bore is the same but I'm just scared the rod length might be different. Thanks!

 

no, you need to rebush the rod for a floating wrist pin.

 

yeah joel is right you have to have the rod modified to accept the floating wrist pin that the type s pistons use. the normal wrist pins are press fit. if you search there are a bunch of thread for putting type s pistons in h22.

 

ok i have a question about this too. Let's say I wanted to go OEM Type S pistons, the factory ECU on the 97's wouldn't feed it enough fuel w/o chipping or doing something to the ECU correct? I mean it wouldn't even be a good idea to try... so what's the # for the Type S ECU, and do you know any place that carrys them just to see a price?

Still haven't decided if I want to go FI or NA, but I really need new pistons/rings reguardless.

 

as far as i know putting in higher compression pistsons does not require you to change the amount of fule you put in, mayb ein a extreme case, but timing would probably be more important. in any case its kind of like putting on a CAI header and exhaust without tunning. there will be some gains but not as much as if you were to take it to a dyno and TUNE it. If you put in the type s pistons there will be some gains, but best gains will result with tuning. you would not want to use the type s ecu with just the type s pistons. the type s has different cams, intake mani, and other things that you don't have.

 

Air/Fuel ratio is determined in closed loop by feedback from the o2 sensor... The difference between the two pistons won't be enough that the stock ECU can't correct. And in open loop, Preludes run rich as hades anyway, so you should be okay

 

Whoops, I forgot to say. The 98+ Pistons come with the rods already attached which are floating type pins, not the pressed ones like the 92.

 

i believe there are also 2 kinds of pistons for the h22, piston types A & B. each block has a different piston config, and it's stamped on the block. thing is each block is different. so mine could be abba while yours could be aaab, etc.

what most people do when going to a type-S piston is get the A pistons (which are slightly bigger) and use 4 A's and hone whatever cylinders were B piston. or they get the .25 oversized and do the same thing.

 

USDM type S pistons?? better make sure you know what you are getting before you buy it. Never had a type s is the US.

-Jeff-

 

All you need to do is pick up soem type s pistons with a stock bore size and have them put on to the stock h22 rods by a machine shop rebused for a floating wrist pin like someone has already stated. They will work just the same as the stock pistons and rods but higher in compresion. Have them on my 92 jdm h22 block with nothing special done besides for the rods and pistons.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bad-monkey &raquo;</TD></TR><TR><TD CLASS="quote">i believe there are also 2 kinds of pistons for the h22, piston types A & B. each block has a different piston config, and it's stamped on the block. thing is each block is different. so mine could be abba while yours could be aaab, etc.

what most people do when going to a type-S piston is get the A pistons (which are slightly bigger) and use 4 A's and hone whatever cylinders were B piston. or they get the .25 oversized and do the same thing.

</TD></TR></TABLE>
I have heard the A/B thing too. My friend had the dilema with his JRSC'ed H22a4 b/c he couldn't see the markings.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tein Man &raquo;</TD></TR><TR><TD CLASS="quote">Whoops, I forgot to say. The 98+ Pistons come with the rods already attached which are floating type pins, not the pressed ones like the 92.</TD></TR></TABLE>

What are you going to do? Re-do the Rod bearing sizing for the crank? Unless you want to buy new rod bearings you will be using the 92 rod rebushed. The attached rods probably have different numbers on them

 

Aren't the crank journal size the same for all 92-00 Prelude VTEC? I would just need to find the correct bearing size, no? Does anyone know what clearance(s) are suppose to be for the bearing to crank?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by NirVTECn2o &raquo;</TD></TR><TR><TD CLASS="quote">
I have heard the A/B thing too. My friend had the dilema with his JRSC'ed H22a4 b/c he couldn't see the markings. </TD></TR></TABLE>
don't forget about the .25 over. IIRC the markings are A=none, B=B. The A's are bigger, and the .25 is biggest

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tein Man &raquo;</TD></TR><TR><TD CLASS="quote">Aren't the crank journal size the same for all 92-00 Prelude VTEC? I would just need to find the correct bearing size, no? Does anyone know what clearance(s) are suppose to be for the bearing to crank?</TD></TR></TABLE>

no crank journals are 50mm for 92-97 (YES 1997)
and 55mm for 98-01

But aren't you talking about rod bearings and not crank journals?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rjr162 &raquo;</TD></TR><TR><TD CLASS="quote">
don't forget about the .25 over. IIRC the markings are A=none, B=B. The A's are bigger, and the .25 is biggest</TD></TR></TABLE>

regular are blank (A) or B

oversize are AO or BO

 

are you talking about the crnak journal size or the Big end bore of the rod? as far as i know the Big end bore on all h22 rods is the same, but joel is right the mains bearing for the crank journal changed size from 50 to 55mm

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by prelittlelude &raquo;</TD></TR><TR><TD CLASS="quote">are you talking about the crnak journal size or the Big end bore of the rod? as far as i know the Big end bore on all h22 rods is the same, but joel is right the mains bearing for the crank journal changed size from 50 to 55mm</TD></TR></TABLE>

That's right...rod bore sizes are all the same. Expect the F20B but that really doesn't count.