BlackSRT4

For some reason i cant boost over the max of 13psi..i have an 8psi spring inside the wastegate. I have tried both an EBC and MBC and have max out the settings and is the same thing. Whats the deal? do i need a new wastegate or try and get a higher psi spring? another thing i noticed its that when i shift with or without a BC, boost starts to really build from 5psi and come in slow.... any help would be great...

HatefulMechanic

external gate? try a bigger spring. i presume you have done the obligitory boost leak check and exhaust leak checks?

BlackSRT4

yes, i've checked for boost and exhaust leaks. yesterday i went crazy and t-bolt clamped every vac line... i'll order a bigger spring this week.

BlackSRT4

yes its an external gate

Fabrik8

How long are your lines to the boost controller?

BlackSRT4

the like that run from the boost controller to the top port on the gate is about 3-4 feet long. i thought as long as the vac lines got pressurized, hose length didnt matter.

Fabrik8

Well, that could have something to do with it..
I don't think 3 feet will be a problem though. You have to think in terms of flow, not pressure. If the boost controller can't regulate well because the lines are too small for their length then you'll have a problem. I'm not sure how much flow the controller needs pass to through to regulate the boost. I've heard of boost creep and spiking problems with long lines, because of pressure resonance and poor flow. You might want to try the manual boost controller with very short lines and see if you notice any difference. It may not be the problem, but it's good to eliminate possible variables while tracking this down..

BlackSRT4

i've tried the manual, and i've still got the same problem...just now, boost is consistent and comes in faster.

Fabrik8

Try again with the lines shortened..