Only getting 11 psi,comp 8079,370 ci
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Only getting 11 psi,comp 8079,370 ci
Had the car on the dyno at speed inc today. With the boost controller at 80% duty (aem truboost) and an 11psi spring we are only getting 11psi. Just off the spring is about 7.5psi.
This is a forged 370 with stock intake and ported 241 heads,232/236 cam. Comp ball bearing,80/79 turbo with 1.32 ar and 3.5dp that goes to 3 then cutout.
Could this be back pressure, problem with controller?
Alex
This is a forged 370 with stock intake and ported 241 heads,232/236 cam. Comp ball bearing,80/79 turbo with 1.32 ar and 3.5dp that goes to 3 then cutout.
Could this be back pressure, problem with controller?
Alex
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From my own experience the duty cycle is deceiving, it might be at 80% but at 83% you might gain 2lb's. On my AEM I don't see a single lb of boost above the spring pressure until 70+ duty cycle
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I had a similar experience with the Tru Boost. Duty cucle seemed to give me about half that percent in boost percent increase(80% gave me 40% more boost) The controller worked fine, but the value wasnt a direct indicator.
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I've checked for leaks, could not find any. Is there any chance with a 1.32 going to a 3.5 dp but about 2 feet later going to 3 inch cause to much back pressure and stop it dead on making boost?
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Although it is not an optimal set up I do not believe it would be the cause. I think you keep looking at the turbo as the problem but I think it is something else unless the turbo has damaged bearings.
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Im going to have jim at speed inc try turning the controller up to 90%. If that doesn't work I was thinking of having him block off the waste gate referance, do a very quick run just to see if boost goes up.
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Ok so from what I understand off the supposed 11lbs spring it only made 7lbs of boost but did 600whp.
So thats kinda good news but is really strange that it only made 7lbs with that spring.
So thats kinda good news but is really strange that it only made 7lbs with that spring.