looking for a little wastegate info...I'm baffled! I have an external waste gate setup, I was hoping to run without a boost controller. Am I wrong thinking a 10lb spring, without a boost controller would open at 10 lbs. of boost? I've tried 2 springs, 7lb ans 11lb and the boost is going out of control. thanks (tial sport 38mm...new)

 

you are wrong, a 10psi spring will crack open as early as 5psi but hold boost pressure at 10psi once it gets there. thats why boost controllers are nice because most have a setting to keep the gate shut longer so you can build boost faster.

also, what size turbo are you running, is the boost going above the spring pressure? if so, your wg is too small. a single 38mm is tiny!!!! i run twin 38mm gates. with a single turbo you want at least a 44mm if not a 50mm

and just so you dont get the wrong idea, a boost controller will not be able to compensate for a wg that is too small.

 

That 38 should be fine unless he's having to bleed off a very large amount of exhaust.

I'm curious of your turbo size & what engine it's feeding?

 

have you been on the dyno or have a way of data logging boost? would be nice to see exactly what its doing