Hi all! I have an 07 cooper s with a few mods. I have the aem cai with functional hood scoop, forge vent to atmosphere bov, and I changed the charge pipes with forge ones. My forge fmic is coming next week.

so I got my ultraguage yesterday and was able to see how much boost I was making. The forge comes with 2 springs the yellow which is already in and blue which u can swap whenever. With the yellow spring I saw my boost peak at 7.5psi and after swapping to the blue one today I saw my boost go to 9 something psi and I felt the car hold the boost longer between shifts and it pulled really hard.

on the forums I read people getting like 12-15psi stock. I’m not sure what’s going on. All the connections are good. Any thoughts? Thanks!

 

I think 10-12 psi is stock, depending on other conditions. Perhaps your waste gate is loose?

 

maybe but not sure. The car does have 124k miles on it. This is still the stock turbo so maybe it’s age is starting to show a little.