Do a20a3 pistons have a higher comp ratio then a20a1? would it make any difference?
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Do a20a3 pistons have a higher comp ratio then a20a1? would it make any difference?
the FI does have a higher compression ratio. dont know if its the pistons or the head itself. but sure, higher compression would give more power. i doubt that its very much though.
eh well im just going to replace the rod and put a weber on it then save for the b-swap now that towloud is actually going to get mounts made
It is the FI head that gives the FI engines higher compression.
hmmm when i get a head rebuilt i might put on an FI head then
The heads are the same, it's the pistons that are different.
^^Yep it's the pistons. The A20A4 engine has the highest C/R pistons of the A20 engines.
what about in b20? just saying, you know...
Yea its definately the pistons. The only difference between the heads is the intake manifolds.
Hmmmm... I was told when I put a a20a3 head on my old a20a1 that I would get a raise in compression ratio? Also, I didn't see any real difference in the pistons between a20a3 and a20a1. But then again I don't think I compared them side to side.
i think your thinking of the A18 head.
My mistake.....
I went back and looked and we were actually talking about the difference in cam profiles.
Sorry for the misinformation.
I heard something about cams being different?:dunno:Quote:
Originally Posted by 2drSE-i
ok the cams are different as well. i was talking more like the actual head.
while i cant find the thread, and ill happily eat my words if wrong, now that i think about it im almost positive that the brochure that was scanned for the 89 accord said the FI model has a higher compression head. i think the thread was titled something like "look what i found".
where do i get a20a4 pistons? same as a3? i know th a4 is the jdm versio n
While im not 100%, i believe the A4 pistons should be the same as the A3. The difference between those motors is emissions shit, so i dont see why the pistons would be different.
true. i just want it to be fast until my mounts come in. i pick up a b16 for $75 the other day. :rockon: just needs to be bored and new pistons. might sleevee it idk yet.
Quote:
Originally Posted by 2drSE-i
A3 is 8.8:1
A4 (without cat) is 9.4:1
The pistons are different.
Wow really? My Engine book lists the A3 at 9.3:1 C/R.
https://www.3geez.com/forum/showthread.php?t=66662
found the thread. its 9.1:1 and 9.3:1 according to the brochure
i knew i wasnt crazy.
just get custom ones if you want more hp
to throw in a bit more. I'm pretty sure the 86-87 A20A3's have lower compression pistons than the 88-89's. I know the pistons are different, but even Honda doesn't have the 9.3 (or 9.4) anymore. All oem replacements are also the lower compression.
Unless you are given an 88-89 A3 motor, or at least the pistons, I wouldn't waste the time going to chase them down and installing them with the hope to get more power. That little bit alone won't make much of a difference at all.
