Surging boost....?
Surging boost....? I recently added my second wastegate, 2 46mm precisions. Im running a red 6psi spring right now in both. Today I took the car out actually trying to set my brake pads cuz my brakes are horrible. So i noticed that boost would go to 7psi then down to 4psi then back to 7psi and would keep doing it. I am running the older aem tru boost controller. I played with my settings a few days ago putting the wastegate crack to 5psi and the controller all the way down trying to run as little boost as possible. Do you think this is just a controller setting issue? Maybe need to increase waste gate crack or decrease?
Other issue ive noticed is it seems like sometimes when i let off the gas the car wants to keep going for a split second could this be a BOV issue? I am running the Tial bv50 it had the silver spring in it I just installed the white spring... Am i running to low of boost to have the bov open up all the way? Im just trying to get these small issues worked out before i go back to the dyno for final tuning.
Other issue ive noticed is it seems like sometimes when i let off the gas the car wants to keep going for a split second could this be a BOV issue? I am running the Tial bv50 it had the silver spring in it I just installed the white spring... Am i running to low of boost to have the bov open up all the way? Im just trying to get these small issues worked out before i go back to the dyno for final tuning.
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Joined: Nov 2003
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From: Norn Iron
Read the instructions for the controller, as what you're doing is **** about face.
Set any gain/wg crack pressure to zero.
Then adjust valve duty to achieve your chosen boost target.
Then and only then can you consider raising any crack pressure target. Raising it too high can cause oscillations like you are seeing.
And with only 6psi spring, it's crazy to set a crack pressure as high as 5psi.
Leave it at zero.
The above assumes the gates/control solenoids are physically installed and plumbed in a sensible manner
Set any gain/wg crack pressure to zero.
Then adjust valve duty to achieve your chosen boost target.
Then and only then can you consider raising any crack pressure target. Raising it too high can cause oscillations like you are seeing.
And with only 6psi spring, it's crazy to set a crack pressure as high as 5psi.
Leave it at zero.
The above assumes the gates/control solenoids are physically installed and plumbed in a sensible manner
Awesome thanks for the help, I only set it to 5 because it was on 10 from my dyno day but we were having issues (the reason why I added another WG), so i figured id just cut it in half and see where i was at. Didnt expect that issue thats why I wanted to ask before i did anymore to it.
