legacycentral bbs

How much oscillation while on full boost would be considered normal? Using a hallman MBC with the stiff spring on my TD05. I was doing data logging and noticed it fluctuates ~2 PSI. Can't say I really notice it on my autometer boost gauge (but possibly because I'm paying attention to the road instead). I assume this fluctuation is from the MBC spring bouncing on the wastegate?



Thoughts? Would using the stock boost solenoid help to lessen it?

On a MBC will always fluctuate. The electronic ones don't do it as much because they can always adjust themselves.

I have the upgraded MBC from TurboXS with the bleed valve - supposed to take care of this issue??? but haven't put it on yet...

http://www.turboxs.com/uploaded_images/522.pdf

Where are you measuring boost? Stock vacuum/boost port?

Those numbers come from the MAP sensor via ECU. My boost gauge is teed off the umm front left intake line.