overboost? creep? whats going on????

[Buckracer]

I got my Hands on a moded VNT C/S daytona. the VNT has been changed to a VNT28 though. I took it out for a test drive and the boost was, i guess "creeping" I'm new to the stuff. its like the boost would walk up to about 16psi and then the engine would kinda rev like there was no power behind it. this happened when I shifted gears mostly, like when i hit the next gear and punch the gas it revs instead of putting powerdown, all with the boost still haning at 16psi. Is there a range you should stay in with the turbo or something?

Im not sure if this is an overboost issue, a boost creep issue, me never driving a SERIOUS turbo car before, or something mechanicaly serious.

Aaron

[glhs727]

sounds like the clutch is slipping. if you got boost and the rpm's are up but the car aint moving, clutch. Overboost would be more like fuel cut, and would be like a superbad miss and your head woulod probably hit the windshield. It feels pretty violent. Also 16 psi isn't excessive for as vnt but above normal for a reg. VNT
later,
Cindy

[Will Martin]

The VNT is fine, it's called a slipping clutch! LOL

[Buckracer]

I would think slippage, but its a stick, and it doesnt do it everytime. sometimes it hooks up great. it has had clutch work done (a t3 clutch was put in it) the cars got a recalibrated computer for 18psi, that the reason for the upped boost.

[Will Martin]

Quote:

Originally Posted by Buckracer I would think slippage, but its a stick, and it doesnt do it everytime. sometimes it hooks up great. it has had clutch work done (a t3 clutch was put in it) the cars got a recalibrated computer for 18psi, that the reason for the upped boost.

???????? Okay, so when the clutch was changed was the the flywheel resurfaced? All the symptoms you posted are basically signs that the clutch is slipping. It is a stick, so this is why it would do it. An automatich wouldn't do this, per se.

Tell you what, drive the car in third gear and rev her up to about 5,000 rpm rapidly. Shift it into fourth and floor it. You "should" spin the tires, or take off like a rocket. If the car revs like it's building power but not moving, it's the flywheel turning but nothings grabbing=slipping clutch. When a clutch starts to slip, it will not do it every time. After a while you can barely drive it, because the engine is spinning and you're going no where.

[Buckracer]

ahhhhhhh. slippage it is then. thanks will!

ps. your icon......::shudders::