I知 looking at getting a 38/35mm wastegate, planning on putting a 5 psi spring in it, will it be able to hold that pressure reliably. My max boost will be around 8 psi but for daily it値l be around 5. Thanks!

thats 38mm inlet and 35mm outlet btw

 

It will hold fine but just run 8 the whole time, it's not much.. I take it you will use a manual boost controller with the 5 pound spring..? Use a good quality wastegaste. Last thing you want is it boosting more than your set too.

 

That size is perfect.

 

Depends on the manifold design and size of turbo charger.

 

Yes... this. Big turbos require very large wastegates if you intend to run low boost pressures and avoid "boost creep".

 

Which actual type/ brand of wastegate do you want to buy?
For about $200 you can get one that is reliable for what you plan on using it on.
Placement on the manifold is crucial. If it痴 just on one exhaust runner then it could be a problem even if it痴 a good brand of wastegate.
And the idea to go between 5psi and 8psi using a manual boost controller might be tricky because you just turn a ****, and you might accidentally turn it up too much. You池e better off using an 8psi spring all the time and just not put the engine at full throttle.
Theres lots of variables with turbo set ups. Each component matters.

 

Co-Sign. Depending upon the size of the turbocharger determines what size valve on the gate is needed to properly control boost levels. Your boost reference source will also be a part of that equation. So, the more detail that the OP can give on the turbocharger size used, engine size used, etc, the more precise one can be in getting the desired results.