im lookin at getting a 38mm Tial external wastegate...and my question is about the spring that deturmines what boost level it opens at. the only springs it has are for 7.25 psi or 8.7 psi....and since stock boost is supposed to be 8.3, can I run 8.7 safely with the stock fuel system with a walbro..or do I need to limit myself to 7.25.
Or would anyone suggest a different wastegate that doesnt use a spring to open?

 

It's impossible to determine what the actual boost will be just from the spring selection. There are a dozen other variables how much boost you'll get. If you get the waeker spring (i.e. lower boost) you can always add a boost controller or even just swap in a stiffer spring.

All wastegates use springs. That's how they work.

 

Are you putting this Tial 38 on a stock turbo or an aftermarket one? Keep in mind, that 8.7 PSI on a stocker and 8.7 on a more efficient turbo may NOT be the same thing.