can any one tell me what is the diffrences between a b18 and a b20? I am trying to swap my b20 in my crv for a b18

 

I think they are different in the intake manifold and the B20 has a bigger bore. The Jdm P8R has a better flowing head also.There are more differences 2.

 

Different Intake manifold. You'll need to your LS intake manifold. The head is somewhat the same... but some say it flows better. Also the block is 84mm compared to 81mm LS. The compression is pretty much the same. The factory B20 Oil pump produces more better oil pressure than say a 95 and below LS motor. That pretty much it.
But the block swap is diffenelty worth it. More low end torque. If you decided to put a vtec on it later on. The b20/vtec motor with high compression pistons and depending on other stuff you upgrade could yield between 200+230 hp.

 

which b18?