search gave me a few different answers…
but what is the compression for a 96-98 JDM b20b…is it the 8.8:1 or 9.6:1. i know the b20z is 9.6 and the 96-98 USDM b20b is 8.8, but what about the JDM?
the JDM b20B should yield the same CR as a b20Z 9.6, u know that Japan always gets the good stuff. 
My buddy’s '99 JDM B20B with a LS intake manifold and it had 8.8:1 pistons.
Originally posted by teg92
My buddy’s '99 JDM B20B with a LS intake manifold and it had 8.8:1 pistons.
oh i could be wrong then…
Yup! JDM B20B’s are a real mystical thing! I recommend being safe and buying a USDM B20Z.
yeah thats what im going to do…get the b20z to be on the safe side… 20 hp is a big difference
i have the b20b but i have not checked the compression on it…I would guess that it is the 9.6 because of the fact that all motors from japan have higher hp and plus there is no way i can pull on cars this much with only 126hp@8:8:1 …
leeo
As far as I know, all JDM B20B’s are 9.6/1. Can anyone show me info stating otherwise?
JDM Honda site shows all B20 powered cars as having 9.6/1 cr, including the panelwagon.
-Thomas
Originally posted by brekekex
[B]As far as I know, all JDM B20B’s are 9.6/1. Can anyone show me info stating otherwise?
JDM Honda site shows all B20 powered cars as having 9.6/1 cr, including the panelwagon.
-Thomas [/B]
This was in a '99 JDM B20B my friend picked up. P3F are the 8.8:1 pistons. The engine was stamped '99, even had an LS intake manifold. There was a thread on honda-tech where someone had translated the japanese honda website and showed the 3 variations of b20s available in the JDM. 8.8, 9.2, and 9.6.
ok…thats evidence enough for me…i want the 9.6:1 compression, so im not taking chances with the b20b… its the z for me
Do you know of any way to check the serial number on the block to determine this?? My friend and I are debating what the compression ratio is on our jdm B20’s. We both have them in our tegs, he thinks they’re only 8.8 c. ratio, they’re both out of a 97. Is a compression check the only way to find this out???
Originally posted by teg92
There was a thread on honda-tech where someone had translated the japanese honda website and showed the 3 variations of b20s available in the JDM. 8.8, 9.2, and 9.6.
who me?..
JDM CRV w/b20b
1996:
cr - 9.6:1
ps - 130@5500
kgm - 19.0@4200
1997:
(2wd?)
cr - 8.8:1
ps - 130@5500
kgm - 18.8@4200
(4wd?)
cr - 9.2:1
ps - 145@6200
kgm - 18.2@5200
1998:
cr - 9.6:1
ps - 150@6300
kgm - 18.8@4500
JDM S-MX w/b20b
1996:
cr - 8.8:1
ps - 130@5500
kgm - 18.7@4200
1999:
cr - 9.6:1
ps - 140@5500
kgm - 19.0@4200
2000:
cr - 9.6:1
ps - 140@5500
kgm - 19.0@4200
JDM Orthia w/b20b
1996:
(2.0GX, 2.0GX-S)
cr - 9.2:1
ps - 145@6200
kgm - 18.2@5200
1998:
2.0GX, 2.0GX-S)
cr - 9.2:1
ps - 145@6200
kgm - 18.2@5200
this is what i copied off the jap honda site. Doesn’t make very much consistant sense and i’m not sure if i believe it even tho its from the official site.
For example that orthia car claims a 9.2 cr and it was Newman, i believe, who said he got his b from that car (showed a pic even) and swore that it had the Z pistons in it. So it could easily be a mistake, especially considering the orthia base model had the ls engine in it…
Sooo, i’m guessing its just hit and miss. I’ve been chasing this dilemma all year and the consensus is split. I’m now absolutely certain that some are the highs and some are the lows. No idea how to tell externally, except, the 8.8s should have about 160-165 psi’s sombody said and the 9.6’s should be 20 pounds or so more i’d guess (anybody?). When i order mine i’m just going to go for the newest one possible and cross my fingers.
btw, the 8.8cr b20b will make more than 126hp in the ls engine bay. That tall crv intake man. is a real hp robber. they say 1 full point of compression increase is worth 7% of power…
d
Hmm… I have a hard time believing the 9.2:1 compression.
I see little logic in offering essentially the same engine with 3 different pistons. I can accept the evolution from 8.8:1 to 9.6:1.
Then again… weirder things have happened.
As I still have not cracked the head off my block, I cannot say with certainty what pistons my B20 has.
But with my power output (140whp) and the compression readings (190-195psi across all 4 cylinders), I believe that I have the 9.6:1 engine.
Will know soon enough.
-Thomas
brekerex, do you know which car your b20 came from? what year is it?
One possibility i’ve considered about that 9.2:1 cr version is perhaps it could be the z pistons with a deshrouded 84mm combustion chamber. I’d be surprised if they bothered tho, and i still maintain that its probably some typo mistake. But, as you say, weirder things have happened, 'specially in Japan.
d
this subject is getting everyone fired up
http://www.honda-tech.com/zerothread?id=179188