external wastegate sizing

[00tegGsr]

I am about to buy a tial wastegate for my t3/t4 hybrid and I have heard that if you do not get the correct size wastegate for your turbo application you will get mad boost creep. I was wondering how to determine this is there some kind of a chart that anyone has that can explain this? Also I am getting a profecb II boost controller and am going to run 1 bar on 93 octane daily, my question is about wastegate springs. They offer them from like 6psi to 24psi, can I get the 24psi spring and use my profecb to dial it down to 14psi ? Or do I just have to get the specific spring for however much boost I want to run?

[boosted331]

Originally Posted by 00tegGsr

I am about to buy a tial wastegate for my t3/t4 hybrid and I have heard that if you do not get the correct size wastegate for your turbo application you will get mad boost creep. I was wondering how to determine this is there some kind of a chart that anyone has that can explain this? Also I am getting a profecb II boost controller and am going to run 1 bar on 93 octane daily, my question is about wastegate springs. They offer them from like 6psi to 24psi, can I get the 24psi spring and use my profecb to dial it down to 14psi ? Or do I just have to get the specific spring for however much boost I want to run?

I'd run a 38 or 40MM tial for your application. You pretty much can't go too big with your wastegate(s), but you can go too small. Tial sells tons of springs for their wastegates starting at like 3 psi and working their way up to 20+. If you run a 24 psi spring in your gate the MINIMUM boost you can run would be 24 psi. You can dial up the boost from your wastegate setting, but you cannot dial it down, unless you have a CO2-run controller.

[00tegGsr]

Alright so are you saying I could just get a 3psi spring and use my profecb to dial it up from 3psi to 24psi if I wanted to? Because I only want to run like 7 psi when I am just driving to work and stuff and when I race I want to dial it up to 15 psi. Which spring should I get to do what I need?

[mrchaos]

yes, go for a spring on the lower end of your boost range

use your controller to go up from the spring boost pressure