I'm running a J-spec Turbo II in a Kit car. I didn't get the blow off valve with the engine. How important is this if I'm only running stock boost? At what pressure does the stock valve open? Would it make a lot of difference on which side of the intercooler I mounted one?

 

You should really run one. Either side of the IC is fine. Usually the closer to the TB the better. If you can't find one I should have one lying around.

 

Thanks for the offer, but I think I found one from a '93 for a good price. I'll use that until I buy an aftermarket one.(they seem kind of expensive for what they are.)

 

The stock BOV will do ok up to around 12-15 PSI. After that you should really go with an upgrade.