Post a picture of the wastegate. If it's a 35 and not a 38 the small red will yield 6.5psi and would probably creep a bit.

What paint is on your original spring?

 

I've had plenty of 35 two bolts and even Deltagates that were 35mm. No issues with creep there.. That was in the ignition timing, if any showed

 

I am just more interested in why a cheap spring can cause this problem, especially when it doesn't mind, fits properly, and feels softer.

Sorry, but the conclusions from the OP makes no sense at all, even if the spring was made out of plastic. You see, a cheap spring will just make no boost at all, not the other way around...

Regardless, I think it's poor observation and troubleshooting. In this case, just swap in whatever works and fix th issue. Can't draw any technical conclusions in this particular case, unless we are missing a big piece of info...lol

 

Yup

Still waiting for him to start testing parts

 

The reason I made this post is because it boggles my mind how a spring could have this affect as well.
It's just a spring. Same height. Tension feels softer. But I swapped them out probably 4 times and always the same affect. 7.5psi on the tial "5psi" spring. And over boost like a **** on the "4psi spring"
I felt the same. It's just a spring. I don't get it either.

I will test soon, it's been cold as **** here lately so haven't gotten the gumption to try it just yet. But I will before I go any further.

 

Again show us a photo of your waste gate and tell us what color your TiAL spring is.

It sounds like you have a 35mm gate as none of the TiAL springs will yield 5psi on a 38mm gate. If your gate is actually a 38mm and you're making 7.5psi on your original spring then it has to be a small green. If your "4psi" spring doesn't have yellow marking paint then you don't have the right spring.

It still sounds to me like you have a 35mm gate

 

Update!!!

Alright guys. I finally got around to testing things.
And sure enough my tial small red spring opens at .5 bar.

The other spring I bought with a compressor didn't even budge until 1bar!!!!

I had a buddy lend me his .4 bar spring and I threw it in and perfectly hit and held 5.8psi.

All is well in the world,
I'm not sure if this means much but on my cheap 4psi spring it was the same height as the tial but had more coils than the tial did. I sent a 5lb dumbbell on each spring and the tial compressed more than the other.

What is weird is I emailed tial and they told me if I had a 5psi spring and my manifold pressure was more than 1:1 which is common this could change the pressure the spring gives.

Thanks for all the help guys