I was talking to the GIAC dealer in SLC, and they told me that the J valve wouldn't do much unless your car was shaking and not handling the chip very well. I heard it adds a couple psi to the boost, but he says you might get 1 psi from it. Is it worth getting if my GIAC is handling ok in my car?

 

I had the N75h valve and it was a huge difference, it was alot more responsive and so much smoother

 

so which one is the best one to improve power the "h" or "j"???

 

I think it depends on the year on my 99.5 the H was insane and worked great but then others have probs with the H so i dunno for sure, I read some testing that a guy did on his car and he found the H was best for him too