Not really a n00b to turbos and this is probably a simple question but i can't think of the answer. What actually controls how much boost you're limited to? If the spring in the wastgate is set at like 10psi and you set you're boost controller to 11psi will it actually make that much boost or will the wastgate open and keep it at 10? Technically then you would want a wastgate with a higher psi spring and just limit boost through the boost controller? Wow im on H-T thinking about this instead of doing my damn english paper, stupid college. Thanks

 

It doesn't matter what the WG is set at.

If the boost controller (bleed off valve for example) is set at 9psi (What mine is at right now), it isn't going to let any psi go through until it hits 9psi. My internal Greddy WG is set at 7psi. 9psi hits the boost controller, goes to the WG, and bam the WG thinks it's overboosting instantly and opens.

You want the WG lower than the boost controller... WG=8psi, Boost controller=6psi. You hit 6psi @ the controller, it shoots the compressed air to the WG, and the WG just sits there b/c it's not enough air to open it.

jB

[EDIT]

PS, please correct me if I'm wrong external WG guys. I'm talking from personal experience w/ my internal Greddy WG, and it might be different 4 u guys.

 

Your wastegate controls the minimum amount of boost you will run..............the boost controller cannot allow you to run less boost than what your wastegate spring is set for.

The boost controller lets you run higher amounts of boost.
Your boost controller intercepts the boost and does not release it to the wastegate until it reaches whatever level you set the contoller to.

 

Damn I felt so stupid asking this but i had no idea that the spring in the wastegate is the minimum amount of boost you run. Very interesting stuff. Guess you learn something new every day!

 

The boost controller will counter the spring. When you crank the boost controller up it makes the spring act as if it is stiffer. You get to a point where you will run into trouble though. Trying to run 30 psi on a 4.5 psi spring will be tough..soo thats why you want to select a WG spring that is going to be sufficient for the total amount of boost you want to run.

 

hahaa..don't feel dumb, i didn't know that either!