I would think you could run 6 PSI with just an FMU. Of course you'll make more power if your properly tuned, but that will be safe. Anything above 6PSI I would definetly get it tuned.

 

build ur own kit man. easy, and u getto choose ur own parts. and get some 450s and uberdata or crome. ive been boosting 10psi now for a month and its been hitting 12 occasionally in 3rd gear. ask tony (running925) the carruns very well, and will hold its own

 

www.homemadeturbo.com

 

:werd: