350z Evolution Wastegate Spring

Vip350z03 · Tweet this Post! #1 (**permalink**) 05-06-2009, 08:19 PM

Hey guys, I had a quick question....I had my motor built in the fall and am looking to make some more boost now that the summer is rolling around and the motor is a bit more broken in. Does anyone know what psi spring is in the Evolution wastgate for the 350z kit and where I can obtain the one just above that? Also, Any info would help...Thanks

Robert · Tweet this Post! #2 (**permalink**) 05-06-2009, 09:21 PM

The spring that comes with the kit is a 9 PSI spring which gives you 8 PSI at the manifold. To up the boost you'll need to run a boost controller. You can do electronic or manual but I would recommend electronic for its other benefits such as improved boost control and faster spool up time.

Vip350z03 · Tweet this Post! #3 (**permalink**) 05-07-2009, 08:50 AM

The guys at SP had mentioned something about possibly needing an upgraded spring...im currently tuned for 10lbs of boost, and am looking to adventure a little above that. I hate to be be redundant, but I just want to make sure im doing everything right, this is my first turbocharged car let alone with fully built motor, and dont want to make any mistakes. So a simple boost controller is all thats needed to up the boost from my tuned 10psi efficiently?

Also, I only made 360whp and 375 ft/tq with everything mentioned in my signature (motor build includes Pauter rods, Weisco pistons, ARP studs, etc). I was really hoping to make 400whp...could my JWT S1 cams actually be hurting my power #'s? Also, the car was only tuned once after the build...does a second tune and tweaking significantly help increase hp? Thanks!

Robert · Tweet this Post! #4 (**permalink**) 05-07-2009, 05:43 PM

Quote:

Originally Posted by Vip350z03

The guys at SP had mentioned something about possibly needing an upgraded spring...im currently tuned for 10lbs of boost, and am looking to adventure a little above that. I hate to be be redundant, but I just want to make sure im doing everything right, this is my first turbocharged car let alone with fully built motor, and dont want to make any mistakes. So a simple boost controller is all thats needed to up the boost from my tuned 10psi efficiently?

Also, I only made 360whp and 375 ft/tq with everything mentioned in my signature (motor build includes Pauter rods, Weisco pistons, ARP studs, etc). I was really hoping to make 400whp...could my JWT S1 cams actually be hurting my power #'s? Also, the car was only tuned once after the build...does a second tune and tweaking significantly help increase hp? Thanks!

The 9 PSI spring is the highest spring for that wastegate. You could add shims to the spring to increase the boost pressure but it would only get you 2-3 PSI more. A boost controller is the way to go if you want to start increasing boost and be safe about it. Also a tune means everything for power. If you up the boost you should definitely look at dyno tuning the car again to get the best power production possible.