I am wanting to know the difference between the actual (correct me if im wrong)Hitachi US Turbo and the J-Spec version of the turbo(specificly 87 TIIs), same size as far as housing? compressor wheel? Reason i ask is i have found a project car that i am looking at an 87 TII with blown turbo for fairly cheap, well i have also found an 87 J-Spec turbo + manifold for also fairly cheap, would this be to any benefit to go with the J-spec turbo?

 

The turbos themselves are identical. The only difference between the manifolds is the location of the twin-scroll actuator, but it still works exactly the same.

 

how about the s5 motors anydifferences between usdm and jdm? like anything any differences i just wanna know about.

 

Motors are identical as well. The difference is in the downpipe for the US/JDM Market.