high boost

[9192tsi]

i have an evo III big 16 g, header, 3''exhaust out the back, high flow fuel pump, bov, and a manual boost controller...i have the controller to the lowest setting and the psi goes to 14 and when i hit 5000 rpm it goes past 20psi...the controller works because when i raise it, it builds higher boost faster...please advise!

[96TSi]

sounds like you have a leak in your lines for your boost controller.

my MBC is similar.. when i close the valve all the way, i still get like 10psi because of line leaks and so on. you should teflon(spelling?) tape all your fittings and black tape around the splitters. that might help ya some

[EclipseRST]

no he's getting boost creep like a motherfucker... what you need to do is have your O2 housing ported (mainly the wastegate side) see what happens is since he has 3" exhaust there is not back pressure on the turbo so it just wants to keep spooling because the exhaust flows easier that way, and the wastegate cant open fast enought/wide enough to relieve the turbo from building boost so it just continues to boost and boost, so your options are to either get a external wastegate or have your O2 housing ported... the cheapest way is to have the O2 housing ported but the best way is to get a external wastegate and mount in on the manifold.