i want to know what the difference between a jdm b20 long block and a usdm b20 block....i know that the usdm is a short block but was is the difference...thanks

 

There are compression differences, intake manifold differences, and in the newer B20Z's, the heads are totally different (valves, cams, combustion chamber, intake manifold, compression level)

JDM B20 engines only have a letter after the "b" and the "20"

i.e. B20B

They came in three different flavors. (possibly more)

8.8:1 compression (no knock sensor) P3F
9.2:1 compression (knock sensor) P3F
9.6:1 compression (knock sensor, larger valves, combustion chamber matched to the block (84mm)) PHK


USDM B20 engines have a letter and a number after the "B" and the "20"

i.e. B20B4 or B20Z4

The B20B's came with low compression and an ugly tall (sometimes refered to as the Girrafe) intake manifold, usually low compression. Some of the JDM B20's came with them too.

The B20Z's came with a normal intake manifold, some of them even had a weird plastic plenum on the top (which helps with low end torque by increasing the intake manifold volume). From what I understand, the B20Z's are all higher compression (phk-a03)


I have a JDM B20B 97' spec (8.8:1 compression, no knock sensor).

Think of the low comression b20's as Integra LS engines with larger bore (84mm instead of 81mm) because they share the same head (p75).

I would suggest going with an obd2b B20 engine as you'll most likely end up with the higher compression engine.

Hope this helps.

 

the blocks are the same. the internals are different.

 

to the above posts

But to add a little bit to that...
A short block and a long block have nothing to do with where or what the engine is.
A short block is the block, no head
A long block has the head included
A turn-key engine is just that, includes the accessories (hopefully) so you toss it in the engine bay and you're good to go.

Someone correct me if I'm wrong and just made an *** out of myself