kelsey_canard

iTrader: (5)

How close does your boost stay to the target psi? Heres a graph of my boost levels during a log. Bounced around from anywere between 6.5-9psi. How much boost is that considered? Do most people take the low peak? High peak? Average?

Chevy_King1500

iTrader: (7)

somethings not right. should be a smooth line, do you have a boost gauge?

smokeshow

iTrader: (16)

Typically boost will fall off a little bit due to inefficiencies and the turbo not reacting instantly. However your boost curve looks completely messed up... I think there is something else going on. Can you post the rest of that part of the log? I'd like to see RPM as well...

kelsey_canard

iTrader: (5)

I zoomed the resolution in on the boost graph to see the variances better. If you look its only a ~2.5psi variance, but its sparatic. Heres another picture.

smokeshow

iTrader: (16)

Ok, well that doesn't look too bad then... What does your signature mean by 69/77mm turbo? Which turbo is that?

kelsey_canard

iTrader: (5)

69mm compressor/77mm turbine. Its a knock off gt45 ebay turbo. Cheap turbo. I'm really wanting to turn my boost up a little higher, but my boost jumping up 2 or 3 psi on a shift worries me that i might catch some detonation. Think a good boost controller would settle my variances down? Im using a manual boost controller now. Ball and spring type.

smokeshow

iTrader: (16)

No, that compressor is too small. It is falling off so hard because its choked. I bet you can try to turn up the boost and it won't go much higher. It jumps on the shift because the engine suddenly needs less airflow, so it can build more boost. But it will always fall off like that.

kelsey_canard

iTrader: (5)

Alot of people say the limit on this turbo is around 650whp. Surely I would not be choking it yet. Maybe pushing it out of its efficiency? Could this be an indicator that I'm shifting too late?

smokeshow

iTrader: (16)

It might make 650 on a 3.0L, but not a 6.0. And that is exactly what it means when a turbo chokes...the efficiency falls off below a critical value and it cannot recover/build boost.

Ferocity02

iTrader: (59)

My boost has a variation of around 1-1.5psi sometimes, its worse in lower gears when the motor is not loaded as much and thus producing less boost. It falls off slightly near redline.