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Need some help! So ive jut done a TD05 conversion on my Airtrek.
It is all new stock Evo 7 GTA parts, new turbo, 3" 02 housing etc. Using a Turbosmart actuator with a 10psi spring (low boost for tuning first). However in WOT in 3rd best i can get is aroun 6 psi. only running wastegate (3 port not connected)
What I have checked to date:
Boost leak test - holds 22 psi- loosing about 1 psi a second ( i can hear a leak around the IACV / throttle body). 1 psi a second is supposed to be ok?
Wastegate actuator - has 3mm preload. actuator starts to crack open around 10 psi when doing pressure test
BOV - turbosmart BOV stock replacement for evo - piston seems to move fine.
I thought maybe they had put the wrong spring in the wastegate - opened it up and it has the correct 10 psi spring in there...
Cat converter is pretty new - 100 cell
Car drives fine and AF ratio is what im expeting to see from the map - just wont make past 5 psi?
Any other thoughts cause im confused as hell
Last edited by OzAirtrek; Jul 17, 2021 at 11:07 PM.
Reason: images
You have to fix the leaks, start spraying soapy water to help you narrow them down. If it's coming from the throttle body area its likely throttle body shaft seals, biss screw o-ring, or the High speed idle valve seal. The IACV seal could also be leaking, but I think that's less common.
Where are you sourcing boost for the wastegate and where are you measuring boost pressure. Pressure at the turbo outlet is going to be higher than at the manifold, so if you sourcing wastegate pressure from the turbo outlet and reading it from the manifold, you could just be witnessing the pressure drop across the intake system (plus leaks).
You have to fix the leaks, start spraying soapy water to help you narrow them down. If it's coming from the throttle body area its likely throttle body shaft seals, biss screw o-ring, or the High speed idle valve seal. The IACV seal could also be leaking, but I think that's less common.
Where are you sourcing boost for the wastegate and where are you measuring boost pressure. Pressure at the turbo outlet is going to be higher than at the manifold, so if you sourcing wastegate pressure from the turbo outlet and reading it from the manifold, you could just be witnessing the pressure drop across the intake system (plus leaks).
Thanks mate. Yeah I am definitely seeing the drop across the intercooler .. wastegate is sourcing from compressor outlet and gauge from manifold. Still 5 psi seems excessive right?
What sort of of leakdown rate from the pressure test is normal?
