roller bearing turbo problems ???? help!!

[daz]

purchased a roller bearing turbo from universal turbos a direct replacement for the oem unit same size housing just slightly bigger compressor and exhaust turbines. with the original(now knackered) turbo the peak boost was at approx 3800rpm on the rollers nothing changed bar the turbo and now the peak boost is at approx 5000 - 5500rpm. took the car back to john noble motorsport where they took the turbo off checked the wastegate and the general apperance and fitting of it and said it was fine, put the oem actuator back on and the car is still not getting to full boost till 5000 ish rpm????????? :shock: anyone have any idea why this is??? could it be the trim on the turbine or something else. ps car was still running roughly the same horsepower as with the oem unit but because the boost is not reaching its peak until much later the torque has dropped by about 30 llb/ft........... ideas :shock:

 

[Fast Guy]

Ring Universal and see if they have any ideas.

 

[skiddusmarkus]

Maybe the wastegate is creeping open?Is the rod exactly the right length ie has it been incorrectly adjusted?

 

[Fast Guy]

Is the wastegate free to move? I got a turbo back once that had been overhaulled and it was stuck until I freed it up. Fortunately I noticed before I put it on the car.

 

[daz]

john nobles have checked it all over the wastegate is fine the actuator is fine its not stiff not catching on anything rang universal they have less of an idea than i have so im pretty much confused guys

 

[daz]

plus fast guy the turbo has not been overhauled its brand new ????

 

[daz]

no ideas then ???????

 

[daz]

simon put the oem actuator on today off the old turbo which has not moved and its exactly the same and this was fine on the old turbo. turbo is fine and free and can hear it still spinning for about a min after i turn it off. could it be the trim off the turbine wheels which is incorrect or poss meant for a higher power car ???

 

[MORRISMINOR GTI-R]

whats the spec of the turbo?

 

[zia]

post up your exact turbo spec? and how are you controlling boost? no air leaks etc i presume? have you changed anything else on the car since is it set up correctly?

zia

 

[daz]

the turbo is a t28 standard housing machined out on the inside to fit slightly bigger exhaust and inlet wheels purchased from universal turbos. and yes no oil leaks or anything done the ecu fault code check came up 55 was basically old turbo off new one on. been to john nobles they say that the installation is fine. i do not know the exact spec ie trim of the wheels ect. i know that its not the actuator or the pre load on this as i have had it all tested... is this just the way that they are or is it faulty and being as im in the midlands and the company is in southampton then its a bit of a trek and a ball ache if it is faulty

 

[daz]

but 2000 or so revs later than the oem one seems a bit much to me ??? pretty much stuck to be honest. tried it for a second with the actuator pipe off today to see how long it took to reach its max operating boost of 1.2 bar and is exactly the same. prob is that this is my everyday car and its looking like the turbo will have to go back to universal ffs

 

[daz]

controlling boost through the unichip boost controller at the moment and standard boost solenoid but thinking of replacing that with the blitz unit the new one .

 

[Fast Guy]

If you're thinking of sending it back, put your old one back on and if it's back to normal, it must be the RB turbo at fault. (trim or otherwise)

 

[daz]

bit difficult being as the other ones knackered so no go there im afraid
its coming off and going back monday