GraphiteAccord

I heard you say awhile back that the ;92-96 motors were not FRM coated, and you could bore them/put in forged pistons without aftermarket sleeves...is this true? What leads you to believe this? Any pictures?

PrecisionH23a

Here is what happens though if you dont sleeve and run an aftermarket piston in an H series motor






Ask anyone who wants to build a motor right the first time, they will recommend in sleeving the block.

https://honda-tech.com/zerothread?id=317430

https://honda-tech.com/zerothread?id=222772



[Modified by GudeH23a, 2:56 AM 11/18/2002]

VaporTrail

correct, the 92-96 blocks are not FRM coated. This is easily discerned from the 97+ blocks that are, as they are open decked (as shown in picture) while the older blocks are closed deck.

fastludeh22

iTrader: (1)

ok, well im looking in my 93 helms book and i quote "The cylinder block is made of aluminum alloy using fiber reinforced metal (FRM) sleeves" page 5-3 in the engine section

it also talks about it on page 5-14...i'll quote that too if you like


[Modified by fastludeh22, 3:23 AM 11/18/2002]

apexii

I hate to disagree, but they are. Didn't the open deck blocks start with obd2? Having the closed deck does not indicate a different cylinder material.

Robb

All the H blocks are the same, I ran Forged pistons in a 94 H22 bored .040 over and got the exact same results as Gude H23.

boomslang

All H-series blocks have FRM sleeves.

FRM is NOT a coating. It's a material that is an integral part of the entire sleeve.

PrecisionH23a

I was never stupid enough to run forged pistons in the stock sleeves, i used darton sleeves and never had ONE problem. I did my homework

VaporTrail

interesting. I've put pistons in H22's with no problems, but only the closed deck ones.

Suprdave

Does any of this have to do with the tighter clearances of the H22a Pistons?

I believe they run a Piston-Wall of .001? Those JE Pistons, etc...cant run that close of clearances...therefore scuffing, etc.

Suprdave

GraphiteAccord

Vaportrail, can you explain some stuff...what pistons, what was your piston to wall clearence, how much over bore did you do, what rings, what kind of break in time/process. Also, what wristpins you used. if anything I'll just send my block to you and you can assemble the bottom end? will you garruntee anything?

ichibanjap

iTrader: (1)

Bump, because i am curious to know too.

BoostedH23a1

IT DOESNT WORK

GraphiteAccord

do you have experience with this boostedh23? iVaportrail has, he claims to have done it, and he is a creditable source of info.