steve
DSM Wiseman
- 17,253
- 3,922
- Feb 3, 2002
-
St. Charles,
Illinois
eclouston said:This was just a thought but could the stock exhaust have so much back pressure that the wastegate wouldnt open causing me to have this boost proublem.
Not that I know of. It's my understanding the exhaust back pressure helsp equalize the flow differences between the big outlet on the hot wheel and the smaller wastegate outlet. The backpressure isn't going to hold the wastegate shut. The actuator is trying to hold it shut againt the exhaust pressure in the turbo housing. Once the pressure exceeds the spring in the actuator housing the wastegate will open. Boost creep is when the wastegate has opened but the gasses won't flow out the passage, prefering to push their way out around the hot wheel and spin up the compressor on their way out the larger opening. The problem usually happens then you lower the backpressure in the exhaust, like when you go from stock to a 3" exhaust.
Have you made sure that the actuator is working correctly by applying air pressure to the nipple. It should open the arm at about 10 psi.
Steve
...You have to get to these meets too