Holding more boost at redline
#16
have you tried the help spring? there is a how to in the engine section...
https://www.evolutionm.net/forums/ev...pring-mod.html
https://www.evolutionm.net/forums/ev...pring-mod.html
Would upgrading the actuator do the trick?
Last edited by xmaciek82x; Feb 8, 2011 at 07:03 AM.
#18
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It is possible that your setup is out flowing the turbo. If you had a turbo speed sensor you could get a better feel for what is happening based on shaft speed. My setup has the same issue with holding boost to red line as seen in the graph below. Boost hits 24psi, but then drops to 19 by redline.
I pressure tested the car well past 30psi with no leaks. I may try removing the stock BOV to see if there is some dynamic that cannot be simulated with the pressure tester. My car has bolt-ons with no tune(except modded MIVEC map) using Greddy Profec B boost controller.
I pressure tested the car well past 30psi with no leaks. I may try removing the stock BOV to see if there is some dynamic that cannot be simulated with the pressure tester. My car has bolt-ons with no tune(except modded MIVEC map) using Greddy Profec B boost controller.
#21
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If the backpressure in the turbine housing is higher than the wastegate can handle it will be forced open regardless of where the boost controler is set. This is why larger exhaust wheels are necessary sometimes to achieve more power and boost with the sacrifice of a slightly slower spool.
#22
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It is possible that your setup is out flowing the turbo. If you had a turbo speed sensor you could get a better feel for what is happening based on shaft speed. My setup has the same issue with holding boost to red line as seen in the graph below. Boost hits 24psi, but then drops to 19 by redline.
I pressure tested the car well past 30psi with no leaks. I may try removing the stock BOV to see if there is some dynamic that cannot be simulated with the pressure tester. My car has bolt-ons with no tune(except modded MIVEC map) using Greddy Profec B boost controller.
I pressure tested the car well past 30psi with no leaks. I may try removing the stock BOV to see if there is some dynamic that cannot be simulated with the pressure tester. My car has bolt-ons with no tune(except modded MIVEC map) using Greddy Profec B boost controller.
Omg is your afrs correct 15.0 to 14.1??
#23
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To the other person crush your bov that helped me just remembered but dont over due it use a vise grip or take it off the car and press it even both sides not just the middle that would cause it to leak.
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Achilles, thats boost not afr. You might not be able to hold anymore, your setup might flow exceptionally well like someone else already said. If more heat comes, its not worth it. Torque might go up but power up top will fall off faster.
#26
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If the backpressure in the turbine housing is higher than the wastegate can handle it will be forced open regardless of where the boost controler is set. This is why larger exhaust wheels are necessary sometimes to achieve more power and boost with the sacrifice of a slightly slower spool.
My conclusion was backpressures were consistant with boost for both turbos, the only difference was the stocker backpressure became proportional to rpm, furthermore proportional to wastegate load. And the full backpressure remained less than boost
I think some might be posted on the cbrd forum
#27
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If the backpressure in the turbine housing is higher than the wastegate can handle it will be forced open regardless of where the boost controler is set. This is why larger exhaust wheels are necessary sometimes to achieve more power and boost with the sacrifice of a slightly slower spool.
Mikey
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when did this problem start? im not sure if this just started or you noticed it when you were tuning. i would def recommend upgrading the wga. i have a red with the fp wga and its holding 26-27psi all the way through redline