boost control problem?!!
 

hey guys i have a hallman evolution pro series controller that i have installed.
I checked the boost source input and wastegate output lines on the controller and everything is fine. I turn the controller to the lowest boost setting and monitor on my gauge and i see that the boost isnt regulating as it can exceed 10 psi when i want it set at about 8 for now.
Do you think it is my wastegate that has a problem?
I have a stock s5 TII motor, 720 cc secondary injectors, straight 3 inch turbo back, and a knightsports fcd.. Any help would be appreciated thanks guys.
-marvin

Yeah it's probably your wastegate. The stock wastegate doesn't keep up very well once you have a big free flowing exhaust. Search 'port wastegate' or something similar, doing it well usually involves cutting the openings bigger and welding washers to the actuator arm(s) to cover the now larger ports. Takes a little time, but it's definitely worth the safety and control. Pull the hotside cover off to port and have a machine or exhaust shop do whatever portions you can't do. I ported my own and had a muffler shop weld my washer on, they might have charged me like $10 and it was a nice clean weld I couldn't have made with my cruddy 110V gasless MIG welder.

To check, just bypass the MBC and hook the in/out together. That should open the door @ 4 or 5 psi providing the waste gate diaphram is working, but if it goes high, you'll need to correct.

Did you totally eliminate the stock S5 boost control solenoid? If not, then there will be issues.

yeah i eliminated the stock boost control solenoid. I removed both vacuum lines from the tid and wastegate and plugged them. Do i also need to unplug the solenoid from the harness?

Im thinking that the issue might be my wastegate since i have a freeflowing exhaust. But before i jump to conclusions i will test the mbc and wastegate with an aircompressor. thanks guys

even the s5 wastegate will still creep. I had an s5 turbo with the wastegate ported to the flapper and I still creeped bad even with a 2.5" exhaust system (no cat)

Yeah it's good to make sure all your wastegate and bov stuff is working properly, so do that regardless.

Was it ported only to the stock flapper or a larger one that had been added on?

Probably a wastegate flow issue then.

When I eliminated my stock boost control solenoid (unplugged it from the harness and capped off the vacuum lines) and my car wouldn't boost! You plugged up the vac lines and left it connected to the harness and it still boosted fine?

thats a nice vert!! I normally dont like the hd conversion but well done