I was under the impression that they are a different compression, I thought the b20b's were 8.8:1 and that the b20z were 9.6:1. I just read in a archived post that they are actually the same compression??? Can anyone shed some light on this?

 

the pistons in my 1996 JDM B20B have p3f stamped on top of them.

ie 8.8:1 compression...

this is all i am saying on this subject. (maybe)

t..

 

B20Bx (USDM) - 8.8:1 - 97-98
B20Zx (USDM) - 9.6:1 - 99-00
B20B (JDM) - 9.6:1 - 97-00

 

For sure without a doubt? I have a JDM b20b that I got from http://www.hondamotorsonline.com...the guy there said it was 9.6:1. The top of the pistons say PF3 though, so I don't know what to think. I was under the impession that the PF3 pistons were 8.8:1.

 

 

does anyone possibly have some pics of the various b20 pistons?

 

this is my block, note the "dished" style pistons.



or this link:

http://www.geocities.com/b20bvtecpre...20blocktop.jpg

i have not persoally seen the z pistons, but they probly arnt dished.

if yours hare the characteristics of the "dish" then i'd safely suggest you have the lower compression ones...

my first reaction to this was to get B20Z pistons, but in Australia - yeah, right!!!!

so im holding out to get some custom Cosworth pistons made up...

t..


[Modified by tinkerbell, 4:25 PM 9/18/2002]


[Modified by tinkerbell, 4:27 PM 9/18/2002]

 

The link wont work!!! I really want to see the pic of your pistons!!!!!

 

im trying! im trying!!!!!!!!!!!!!!

if all else fails - cut and paste the link

t..

 

Okay, I got the link to work!

Hmmmm....Its hard to tell. I know mine have a little bit of a dish. Im at my GFs house right now so I cant check.

Did you widen your valve reliefs?

 

ha ha!

yeah, bad pic i know.

i was hopeing not to have to do hte valves, but i clayed her and the valves actually touched the pistons at the intake valve edge.

this is in part due to 1mm milled of the head.

so yeah, it is at the shop ATM getting done.

last thing before final assembly!

t..

 

How much is if costing you to widen the valve reliefs??? Im going to have to do mine as well I think...right now my head is only milled .020 (about .5mm I believ). Im pretty sure Im going to mill it another .020 though. If I get the b20z pistons I found, my compression will be a hair under 11:1

I know people will say its stupid to mill a head that far, and run cast pistons......you have to remeber though, that we all don't have a money tree blomming in our back yard

 

im not ghetto, im jsut not rich!

anyways, we do what we can and still keep up eh?!

here is my resize valves thread https://honda-tech.com/zerothread?id=274473

it is costing me AUD$20, or about US$11, per piston. (leaving pistons in block)

he is using my B20 head as a guide and is making a cutting bit that looks like a valve to fit into the head and cut the reliefs (i hope it works! he says it will...)

yep, with the p3f pistons and 0.040 shaved head im looking at about 10:1...

t..

 

http://hybrid2.honda-perf.org/tech/b20/b20tech.html

look here..they have pics of b20b and b20z pistons.

from the research i've done on jdm b20s, they are all labeled b20b, but there are different versions..they come in at least 3 different vehicles, with different setups.
the highest i've *heard* are 9.4:1 setups.

 

Thanks!!!! That artical was very informative! According to that artical, the b20 has the same oil pump as the GSR and ITR!!!! Is this correct?

 

the oil pumps have the same part number...

t..

 

Does that mean they are the same? I have heard that the GSR and LS oil pump part numbers are the same, yet they are differemt internaly....not that it maters, I already have a GSR oil pump to put on my b20....

 

B20B has been used extensively in Honda Japan's wagon line up from 95-01.
It was available in 8.8, 9.2, and 9.6 c/r in the following:
Orthia, S-MX, Stepwgn, & CR-V
C/R varies on earlier model depending on drivetrain configuration,
while most 98-01s are 9.6 c/r.
CR-V and Stepwgn has since switched to K20A.

 

Does anyone know how to determine what year block I have?

 

no, but you can work out what year your head is...

look for teh pressed circled numbers on the head, the first number should be the year...

t..