manual boost controller vs electronic boost controller?

[Kim307]

What's the difference between the two? Also how do the boost controllers work? I heard that if you have one you can't no longer set your boost lower than the stock boost. What's the difference between fuzzy logic ones such as profec and evc vs Apex'i AVC-R?Thanks for your help in advance

Jay

[91TSiAWD_Mark]

Boost controllers generally fool your turbo + wastegate and tell them to open later. It all depends on the car too.

Lets say I have a manual one. I tune it at 15psi. Now the stock turbo system in a DSM will only boost up to ~11.5psi. The boost controler fools the wastegate by giving it feedback untill the 15psi is reached then it tells the waste gate to open ("we've arrived at 11.5psi") and vent to the BOV.

On a DSM, you can use a fish air bleeder valve (not reccomended) or a ball-and spring type between the w/g and the BOV.

On a Audi/VW 1.8T, the boost is controled by the ECU, so you need your computer reprogrammed.

An electronic type usually allows you to change boost almost on the fly and to have multiple boost settings.