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B20Z or B20B...What's the difference?

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I'm looking to get a swap, and I'm thinking of starting with a B20 setup and eventually going to a CRVTEC build later on down the road. I know that the B20A is the lemon of the B20 series. As for the B20Z and B20B engines, what's the difference? Is there any?
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they differ in compression, and i believe the b20z was only jdm. i might be wrong about the jdm thing but they have different pistons. i think the b20z has higher compression.
So the block is identical then? Higher compression might not be a bad thing. :D
yea the B20b has a C.R. of 8.8 and is USDM. the B20z has a C.R. of 9.6 but i can't remember if it is an only JDM engine. when i bought mine a year ago. i bought it from a local junkyard. and i saw the engine in the CRV. so i knew the actual milage of the enigne. and my engine was a B20z.
actually now that i'm thinking of it. the junkyard owner. actually owns a few race tracks in Maine and in Canada. as well as junkyards in Both countries. so maybe the CRV i got my engine out of was a CDM and not an USDM. and maybe Canada got the B20z!?!
If i'm looking to go VTEC later on down the road, would the higher compression engine be a better option? I have no plans for boost at this point.
no the b20z came out of the later model crv's.
Ok...this is the info I have gathered about the USDM B20's

B20B- 1973 [email protected] [email protected] 8.8:1 84 89 dohc no 2 1997-1998 CRV
B20Z- 1973 [email protected] [email protected] 9.6:1 84 89 dohc no 2 1998-2001 CRV

As far as I understand, the only differences are the pistons, and the fact that the 98-2001 CRV engines have knock sensors due to the higher compression from the different pistons.

Any other differences?
it looks like you have all the differences now.

on your question on which one to get. i would go with the B20z. here are my reasons why:

-more HP
-the C.R. isn't that high where it would be bad for a turbo setup. if you wanted to lower the C.R. then all you'ld need is a thicker cometic headgasket. but if you do go turbo. i would build the bottom end for sure. since thats the B20's weakness.
-and if you do plan to go N/A with a CR/VTEC then higher the C.R. the better.
-and if you plan to go turbo with a CR/VTEC then lower C.R. the better. but either B20 could get the job done for sure.
if you are gonna rip out the internals, then get which ever is cheaper. 9.6:1 compression isnt that great for NA and the internals really arent strong enough for a lot of boost.
If you change the pistons (and rod bolts) choosing between B20B or B20Z would be irrelivant. I would assume that the Bs would be cheaper to buy since they'd be older. I also believe that JDM B20Bs are the same CR as the B20Zs.
OBD1 Kenobi said:
If you change the pistons (and rod bolts) choosing between B20B or B20Z would be irrelivant. I would assume that the Bs would be cheaper to buy since they'd be older. I also believe that JDM B20Bs are the same CR as the B20Zs.
Thanks for the info. Which VTEC head did you go with on your CRVTEC?
I have an OBD0 B16A head from my first swap.

Upon the install onto the B20B block, I converted the engine to OBD1 as the only exhaust manifold I had was a DC Sports 4-1 header, unuseful for a two oxygen sensor system the PR3 (OBD1 B16A) ECU would be looking for. I used the P28 (D16Z6) ECU as a temporary measure before I got a chip burnt for the Hondata S200 I have. (I also have a JDM P30 ECU but will need to get the surface-mounted components desoldered carefully as it is very sensitive to severe heat.)

VTEC comes on at 4800 rpm and the redline is about 1000 rpm higher than I rev the engine. I didn't build the bottom end so I have to be wary of my rev-counter. The engine feels like VTEC should be set to come on 200 rpm lower and once I put in new higher-compression pistons and ARP rod bolts, I will be able to rev higher. This was my achillies heel at the track. The engine was on it's second "pull" but I had to choose a higher gear before the potential could be realised.

Prior to the car being written-off, the B20B VTEC OBD1 had an estimated flywheel horsepower of 220 and torque of 140 lb∙ft. It also passed AirCare (emissions) on the first attempt and had an average of 32 miles per imperial gallon, the best being 41 mi/gal and on a quite spirited run. I also got away with 87 octane gas but that'll change once the higher compression pistons are fitted.
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Thanks, that just about answers all the question I can think of at the moment. :)
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