What are you guys seeing for boost PSI?

[MWilbur516]

I'm seeing 26psi after my ECM has gone through its relearn process when I load a new tune. When I first load a tune I can boost past 32psi and hold 30psi. Then after 100-200 miles, it settles in to 26psi at WOT. WTF? No matter what I try. No leaks, this is in the computer. Anybody have any ideas? My truck did this with the stock turbo, MTW stage2, Bill from PHP's stocker and the MTW stage 1. Does anyone else see this?

[colonel angus]

I've been told it has something to do with the tune, I.D. tricks it to report less than actual so it won't defuel.

Been fighting the same thing but found my turbo inlet hose is slipping off the front of the turbo. Will have that fixed with a 4" I.D. Silicon Boot on Sat.

Denny

[U235a4]

I run a vxcf9nz strat stock and all my tunes are based on that and I pretty much see 27-29 from the first time it's tuned till even after the relearn. that with non pmax tunes stock turbo and pmax based tunes pmax turbo. maybe not what your looking for but my experiance with my truck at least.

[MWilbur516]

Originally Posted by U235a4

I run a vxcf9nz strat stock and all my tunes are based on that and I pretty much see 27-29 from the first time it's tuned till even after the relearn. that with non pmax tunes stock turbo and pmax based tunes pmax turbo. maybe not what your looking for but my experiance with my truck at least.

Any info is useful at this point.

[colonel angus]

You may have the same issue, look at the front of the turbo, lower left side to see if you can see half the turbo mounting flange, wiggle / twist the tube if it moves at all it's a leak.

Mine will run great then slip off, regardless of how tight i make it and fiddle with the ficm bracket.

d

[bwillis2003]

Never had that issue. Can always hit 30 psi if I roll the throttle right.

[MWilbur516]

Originally Posted by colonel angus

You may have the same issue, look at the front of the turbo, lower left side to see if you can see half the turbo mounting flange, wiggle / twist the tube if it moves at all it's a leak.

Mine will run great then slip off, regardless of how tight i make it and fiddle with the ficm bracket.

d

The tube is good. Like I said its gotta be something in the computer.

[MWilbur516]

Originally Posted by bwillis2003

Never had that issue. Can always hit 30 psi if I roll the throttle right.

But you won't hold it on a sustained WOT run, right?

[U235a4]

I would also ask for strat info since that could also be playing a role in it. from my under standing not all vxcf4XX act the same like wise not all the VXCF9XX work the same. Also does your truck have a MAF or just a IAT1 in it;s place?

[colonel angus]

How do you know you don't have an air leak at the turbo? Adrian was adamant if it can't build and hold 30 PSI I had an air leak on my Stage 1.

Wasn't until I messed with the clamp on the turbo did I find mine.

D