Overboost After Rebuild

[jonn]

[Ralph Wiggum]

I cant find the PN anywhere. A 445963-0007 is an 11.80 Psi,445963-0008 is an 8lb and a 445963-0135 is a 6lb??

[Ralph Wiggum]

Part number comes back to a turbo master TB2028 which is a made under license GT25 ( 709143-0001 core assy) which to me looks to be for a Small turbo diesel (nissan xtrail gets mentioned a fair bit) Where the hell did you get that actuator? It could be 24+ psi if its for a turbo Diesel....

http://www.turbomaster.info/despieces_garrett/711380-0010.php

[arronm]

My car is a nizpro stage 2+ car. Recently had my turbo rebuilt by rotor master and had new exhaust housing put on as old one was cracked. So they ported my wastegate at same time as expected. Turbo is now back on car bit I'm having massive overboost issues.

Tune commands 17.5psi, buts it's going 24+. If I kept my foot into it I believe it would keep going.

What could be the issue? They told me the new wastegate should flow better than the last one. So why is it now overboosting?

I didn't think in this instance a retune of the wastegate duty cycle was needed.

Any input welcome. Thanks guys.

Did nizpro originally modify your turbo, because to stop over boosting they would bore out the exhaust housing giving more clearance to the turbine wheel.

[Mr_4.0]

Yes nizpro originally did my turbo. But it now has a new exhaust housing. And was ported again with new flapper.

Is that what u mean?

[arronm]

No, the new exhaust housing could be the problem as the clearance between the turbine wheel and the housing with be stock now and not bored out. Does you car now appear to come on boost earlier and harder. If this is the case the car just needs to be retuned.

[Mr_4.0]

Comes on boost instant. No lag. It's scary. Even running off spring pressure is makes 24psi at like 3500rpm. Before I back off. It's worse when I run off boost solenoid.

For it to be that bad off spring pressure Im guessing it's a mechanical fault.

[Mr_4.0]

That's in first gear too! ^^^^^^

[jonn]

ah I dunno, they fkd up and gave me the wrong one.

[simmo]

I just put anew exhaust housing on my ba and its overboosting like crazy even on the standard tune

im going to bypass the wastegate solenoid and see if it only makes standard boost but im thinking ill have to pull off the turbo again.I also fitted a new standard actuator from ford.I rang ford today and they said they got the new actuator off another company because ford doesnt sell them seperately.They are getting back to me tomorrow to see if they have supplied me with the correct actuator.Its a sh*t fight for sure

Coupled with this crap with the xcal 1, makes me wanna sell the car.

Edited 17/05/11 09:07 AM by simmo