it may be a stupid an question but I just want to know
I got a bare gsr block my question is can I swap everything from the B20 to the gsr not the crank or piston ?

 

You probably want to use the crank - GSR has an 87.2mm stroke whereas the LS/B20 crank is an 89mm.

Which pieces specifically were you looking to use? Obviously the pistons wont work (as you know), but the rest is the same as any LS block

 

So i so I can use the B20 crank on the gsr block and everything else like oil pump and little things like that ?

 

Just depends on what you plan on doing with it. youll need a gsr oil pump and water pump to avoid cavitation.

 

And you remove the oil squirters in order to keep the from damaging piston skirts due to vibration. (Purchase a Golden Eagle Oil Squirter block kit).

Here's an example of when I did mine..
(God. I can't believe I did this almost 9 years ago.. Still have the car, too..)

https://honda-tech.com/forums/all-mo...es-na-2458563/