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I had a turbo blow on a GTR.

Never compression tested before the turbo blew, but after it blew it started having severe blow by.

Compression tested less than 125psi on three cylinders that corresponded to that turbo and 140psi on the three that didn't.

I assumed it was related but can't back that up.

Have always been scared of blowing turbos since, yet have been informed by many people running single turbo's who have blown turbos they had no dramas.

Compression test for starters, will help answer your question.

I had a turbo blow on a GTR.

Never compression tested before the turbo blew, but after it blew it started having severe blow by.

Compression tested less than 125psi on three cylinders that corresponded to that turbo and 140psi on the three that didn't.

I assumed it was related but can't back that up.

Have always been scared of blowing turbos since, yet have been informed by many people running single turbo's who have blown turbos they had no dramas.

Compression test for starters, will help answer your question.

Yep.. I have posted on here a few times about this type of thing.

Some don't believe it, but I have seen it happen enough times to know it does.

Only with Ceramic turbos.. and no idea what causes the dust to suck back into the engine. Causes some nice damage though and only to the 3 cyl that the turbo was on. I'm talking large gouges in the bore.

I was always careful with my GTR's with stock turbos after seeing this.

dude I'd be leaving the car off!!!!

And pulling off the head to check for damage maybe a compression test would be a good idea. before taking off the head.. :)

Have you looked at the turbo?

My car made a bang and ran like poo it was just blowing smoke and run like a pig above like 2000rpms tuned out to be a intercooler pipe came lose.. made heaps of noise!!!

Hope all ends up well...

Hey guys, got it fixed today, got a new high flowed gcg turbo. The wheel was shattered, they took it out from the middle thinggy in the exhaust.

i went from a 276 hp to 311 hp, 206kw to 232.2kw

I am very happy, the car is really powerful

All thats left is the exhaust all the way through and the injectors

Edited by the_game

just throwing ideas out there:

- 20psi of exhaust back pressure at full boost in your GTR (guesstimate)

- exhaust wheel dies, jams against turbine housing

- exhaust back pressure spikes horribly because total exhaust flow from those 3 cylinders just took a huge dive

- big back pressure = big ping, massively hot exhaust residuals left in combustion chamber on next compression stroke causes pre-ignition

- 3 cylinders get blowby, ring damage etc

i can't really think of another reason that the rings and pistons would be damaged if a turbo let go in a GTR. it would be very improbable that ceramic dust/chips/fragments would somehow make their way back into the combustion chamber through the exhaust runners and valves. especially for it to happen equally on all 3 cylinders.

just throwing ideas out there:

- 20psi of exhaust back pressure at full boost in your GTR (guesstimate)

- exhaust wheel dies, jams against turbine housing

- exhaust back pressure spikes horribly because total exhaust flow from those 3 cylinders just took a huge dive

- big back pressure = big ping, massively hot exhaust residuals left in combustion chamber on next compression stroke causes pre-ignition

- 3 cylinders get blowby, ring damage etc

i can't really think of another reason that the rings and pistons would be damaged if a turbo let go in a GTR. it would be very improbable that ceramic dust/chips/fragments would somehow make their way back into the combustion chamber through the exhaust runners and valves. especially for it to happen equally on all 3 cylinders.

I have to disagree. That engineer can say what he likes, however you still have either an internal or external wastegate which limits the exhaust manifold pressure. Although this pressure would be higher than previous.

You can still get cermaic wheel pieces or dust swept back into the cylinder. Especially during valve overlap when your exhaust manifold pressures are much higher than your intake (increased if your turbo is broken: greater pressure differential).

While your engineer is correct that increases in EMAP will increase residuals during the next cycle, its unlikely due to the fact your wastegate would still relieve the EMAP close to normal operation and the compensation by your ECU is still most likely within its limits assuming your lambda sensor is in and working for feedback control. :laugh:

I can think of plenty of other reasons why a turbocharger would damage your engine. Mechanical contact from compressor pieces. Hydraulic compression of fuel from running too rich and incomplete combustion outside of ecu compensation (which is limited)....

Edited by AndrewD

At the risk of sounding simple...

The question was:

- 'resulted in a blown engine'.

He did say from stuff going inside the engine, but I'll take one step back from that and say, who knows exactly why

- BUT

The answer from experience seems to be, and I'm sure others will back me up:

- On GTR's that have blown stock turbos, it is quite common to have failure on the three corresponding cylinders.

I never looked too much into why, so at the same time, it may only be the case for twin turbo's... could that be a possibility?

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