I installed my MBC and i'm pushin 18psi. Now whenever I go for a drive I get huge boost spikes at low rpms and I can't seem to stay at one speed. I try to go 25mph but when the turbo kicks in, it wont stop boosting and I have to let off the gas and coast. I'm not pressing harder on the gas, I keep the same pressure on it but as soon as the turbo kicks in, it spikes and i'm gone. Why is this? how could I make it more gradual into 18psi?

 

What kind of MBC did you get?

Josh

 

Sounds like you have a ball and spring mbc. Boost is more on/off with those. Bleeder style mbc's make the boost come on more gradually. Both will build boost quicker than if you were just using the n75 like stock though. It also sounds like youre confusing spiking with seeing peak boost more easily/often. Spikes are anything over "normal" peak boost. The stock n75 is prone to causing spikes because of the constant corrections that are taking place between it and the ecu. The math isn't always perfect, especially at wot. Purely mechanical MBC's like yours are much more simple but give a more on/off feeling of boost delivery. Bleeder mbc's sort of give you the simplicity of a ball and spring with the driveability of the n75. If youre not using a bleeder mbc now, I have one Ill sell to you for real cheap. I was getting random throttle cut when using it. Too much tq apparently. I dont think this would not happen if it was used in a non chipped car. PM me if you want it.

 

get a turbo xs hpbc thats exactly what you need... its a little hard on the piggy bank but worth every penny. Plus plenty of people use it including cincytt...