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Help! Turbo boosting 12 psi with wastegate fully opened - 6G Celicas Forums

Topic #96365 7 posts Started by huntsmcgee2
So every since being boosted on my 7afe I have never been able to lower my boost past 10-12 psi I kept changing out wastegates no real effect. I decided to just unhook the wastegate auctator and leave the wastegate always open thinking I might see a pound or so I'm still seeing 10 and 12 from 2nd to 3rd shift its an auto. How is this possible.
There really isn't much you can do, what you are seeing with the 10-12 lbs is the lowest form of boost that turbo will produce due to the internal Wastegates operational capabilities. The best option you have in my opinion is external waste gate instead of internal.

This post has been edited by 4-eyed-freek: Jan 7, 2016 - 6:54 PM

It takes 8,460 bolts to assemble an automobile, and one nut to scatter it all over the road.Celica: The name is derived from the Spanish word for "heavenly" or "celestial".Back-2-Back July COTM 15&16
Kinda figured, any clue why a standard t25 would do this.
I doubt anything is wrong with the turbo, wanting a lower boost pressure is the problem. I would suggest a smaller turbo and and external wastegate.

It takes 8,460 bolts to assemble an automobile, and one nut to scatter it all over the road.Celica: The name is derived from the Spanish word for "heavenly" or "celestial".Back-2-Back July COTM 15&16
thats just all the turbo can bleed off. there might be a blockage on the internal wastegate. it could be a number of things.

im more worried about you pushing 12psi in a 7A-FE.

2001 Celica GT-S Turbo1997 Supra TT 6speed1997 Celica 3MZ/1MZ swap1990 Celica All-Trac
Well that's the whole reason for me needing to get this under control I want to run 7-8 psi but the engine seems to enjoy it regardless and I don't hear any knock running -8 static retard and 93 at 10.5 afr. But since I found my wastegate was the problem I don't let it spool past 9 if I let it shift it will then spike to 12.
I wonder how did you run the oil feed fitting to where the oil pressure sensor was? Did you tap the hole or got a specific fitting for to thread in?