PSPEC

Someone please tell me if this will even work without the pistons smacking the head or valves. Factory h22a4 is 10 to 1 compression, so what will it be with the f23a crank and rods shoving the piston up higher out of the hole.
Any thoughts on boring the F23a past its recommended service limit? 86mm is 3.3858 inch. Honda maks pistons that are .5 mm oversize which is 3.4055 inch

Would it really hurt to bore out to 87mm which is only 3.4251

Thats only about .020 more and really only about .010 on each side of the wall since its round.

I'm considering doing the G23aVTEC but I don't have funds to boost it now and I would hate to lose power by dropping my compression when using the H22a head on the F block. I have OEM h23a and h22a pistons here that I can use if I over bore the block. So if the H22a pistons will raise the CR too high or smack the head, maybe the H23a ones will do the trick. I really don't want to raise my compression any higher than prelude type s pistons in H22a (11 to 1)

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Original US manufacturer of replacement short throw shifters for cable shifted Hondas.

Zbone

On the boring side, I'd suggest looking into sleeves if you are going to put that much effort into the build (even though you are using stock pistons). That would help insure the bottom end a little.

Everything else? No idea.

SoCalude98

If you plan on turboing it later on down the road dont ever bother with the F23 crank and rods and or F23 block.

Cylinder pressure is already a haunting factor with the horrible r/s ratio the F23 crank and rod combo yield. That teamed with a thin sleeve and boost is going to go boom fairly soon.

A sleeved H22 block with the 90.7mm stroke and 5.630 rod is your best bet.

You dont need stroke with boost.