yes i agree but i mean i thought that the turbo was god to like 10- 11 psi becuse if you think about it is a veary large stock trubo it is almost like a t03

 

Well, if it helps, my S5 TII, which I purchased new, and now has 20,000 miles on a Mazda reman, pushes 10/11 psi (G Force ecu) and will drop to 8 at the upper rpms. This is with a stock intake (Apexi made no difference), 2.5" Bonez DP and Bonez hi flow cat with the factory original cat back system. I will be putting a Hallman boost controller on in the next few weeks, and experimenting with the boost solenoid also to see what boost changes might be.

As you can by the numbers, the factory turbo will push more than the 4 psi you see.

I have read so many threads about the restrictions of the"small" factory turbo, but have also seen where people are running 14/17 with the same turbo you're having a problem exceeding 4psi. This is why I'm experimenting with various combos to finally decide for myself what the turbo is capable of pushing. The Apexi was only on for a weekend, as I found it made no difference in boost. At least not to the degree that it was even noticeable on the aftermarket gauge.

 

Does it happen in all gears or just first?

The stock turbo normally fades in first, but should keep up in 3rd & 4th.