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Does anyone know of a replacement turbo that can be used on the VQ25DET engine for a streight swap?

Has Anyone had the standard turbo re-sealed or hi-flowed and by whome and how much ?

Any info would be appreciated

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wouldnt you run something similar to what you would on an RB25? a GT2860RS or something? i gots no idea what flange they use on a VQ25 tho.

From what I have found out they are a real ugly looking thing and not similar to the RD25's, There is a workshop in NSW that can modify the turbo and hi-flow it but they can not build a replacement due to the standard configuration and installation issues, I looks pretty tight and hard to remove.

the turbo is an ugly looking thing? or the engine?

im sure its do-able. a highflow will still give you good power gains with the right supporting mods. more boost, bigger intercooler, better exhaust, better filter etc.

Anything iss possible with the right money but depends on how far you want to go. I dont have much more advice being that im unfamiliar with the car. However, do a search for m35+turbo, as i KNOW one has been pulled out of a car here before, and pics were posted up.

Bobbeh

I read somewhere a turbo replacement requires engine out. I saw one method of removing the entire sub-frame and lifting the chassis up, leaving just the engine and front drivetrain behind.

Have a read of this thread;

http://www.skylinesaustralia.com/forums/M3...cs-t192998.html

This may help with the turbo.

What has happened to your current turbo?

Are you aware that be replaceing the exhaust the boost goes from about 0.8bar to 1.0 bar. I think that is the right number or about 14psi. So yu gain a lot of power just with a new better flowing exhaust.

Cheers

Andy

Have a read of this thread;

http://www.skylinesaustralia.com/forums/M3...cs-t192998.html

This may help with the turbo.

What has happened to your current turbo?

Are you aware that be replaceing the exhaust the boost goes from about 0.8bar to 1.0 bar. I think that is the right number or about 14psi. So yu gain a lot of power just with a new better flowing exhaust.

Cheers

Andy

i dont know what is wrong but in to last couple of days i have been getting alot of white oily smoke when i decelerate or sit at the lights. the turbo is not noisy and spools up as usual but i think it may be the exhaust housing seal.

i am going to check it out tomorrow if i get time.

the motor has only done 60k and there was no oily residue on the inlet pipe or the cooler so im a little unsure what is wrong, but the smoke is a little worring.

I read somewhere a turbo replacement requires engine out. I saw one method of removing the entire sub-frame and lifting the chassis up, leaving just the engine and front drivetrain behind.

i dont want to be dropping the engine out just to check out the turbo, i will give it my best try to get it out without doing that.

i dont want to be dropping the engine out just to check out the turbo, i will give it my best try to get it out without doing that.

When I did my exhaust system I got to have a good look at the removal of the Turbo while still on the car...it is possible with the right tools. I have also been quoted in Sydney for a turbo service and it's approx $1,450 for high flow and new impellers(steel). From what I have been told there is no use in making it ballbearing.

P.S. I get some smoke on cold start up but then it goes as soon as the car gets warm(always get up to operating temp before a thrash). Might also mention that these cars need to be running premium unleaded. In Japan I think you might find that our maximum octane is there minimum.

P.S.S. Very strange for the turbo to go at this early. I am running 15PSI(have been doing so for about 15,000kms) on the standard turbo and have no problems

the motor has only done 60k and there was no oily residue on the inlet pipe or the cooler so im a little unsure what is wrong, but the smoke is a little worring.

Hmm I don't get smoke (except when cold) but have a fairly noisy spool and fair amount of oil in all the inlet pipes (had them all off to replace exhaust gasket), does this mean anything bad?

When I did my exhaust system I got to have a good look at the removal of the Turbo while still on the car...it is possible with the right tools. I have also been quoted in Sydney for a turbo service and it's approx $1,450 for high flow and new impellers(steel). From what I have been told there is no use in making it ballbearing.

P.S. I get some smoke on cold start up but then it goes as soon as the car gets warm(always get up to operating temp before a thrash). Might also mention that these cars need to be running premium unleaded. In Japan I think you might find that our maximum octane is there minimum.

P.S.S. Very strange for the turbo to go at this early. I am running 15PSI(have been doing so for about 15,000kms) on the standard turbo and have no problems

I wasnt getting any smoke at start up just after the car was warm

With running higher boost do you have a piggyback computer for the fuel ?

Just an update on the progress of the somokey M35.

Driving home from work I saw my old friend the smoke once the car was warm, realising that I was probably up for a little mor cash I decided to give her a little punishment for letting me down. Got home parked the car and there didnt seem to be any smoke. Anyway I let it cool down as I wanted to check out a few things.

I pulled off the exhaust dump housing off and everything looked ok in there, Some carbon but no oil or anything (not that you probably could see anything anyway) but there was was no shaft play so I put it back together. I also checked the compressor side pipe and again no oil. I checked the turbo drain and egr valve all good. I came to the conclusion that the turbo was actually ok as power was strong and there was no strange noises or anything.

What I did do was check my engine oil level and it was low (Below the low mark on the dipstick) Thre was about 1.6L of oild missing.

I replaced the oil and filter. There hasnt been any smoke since

I have no idea what caused my problem but it seems fine at the moment. I will monitor my oild comsumption over the next few weeks and see how it goes.

  • 2 months later...

Well, The problem with the smoke is all solved. It had nothing to do with the turbo, compression or valve stem seals. It was caused by a faulty PCV valve. Under boost the valve would not seal and therefore pressurise the crankcase and stop the turbo from draining properly and forcing oil out throught the seal into the hosing.

:D

I was also wondering why boost was dropping off at higher RPM's

  • 9 months later...
Nice work. From what I can see almost every M34 owner has problems with boost dropping off at high rpm.

It's designed for low down torque.....not top end.....most turbo's drop some boost by the time they reach redline.

P.S. Highflow fixes the problem.

P.S.S. It also an M35 not 34.

Edited by Jetwreck
P.S. Highflow fixes the problem.

Yeah, one of these days I will get to it!

Do you recommend the workshop that highflowed your turbo?

And just to confirm, did they merely replace your internals or did you go for a new turbo housing?

I would like to keep the turbo externals and just replace the insides.

I would like to keep the turbo externals and just replace the insides.

That is what happened with mine.

I think that Jetwreck and Danwatt's turbos are slightly shorter (if my poor memory serves me correctly).

That is what happened with mine.

I think that Jetwreck and Danwatt's turbos are slightly shorter (if my poor memory serves me correctly).

yea thats right, you end up with a shorter turbo (18mm) when you go for the ball bearing garrett cores, the old school bush bearing T3's dont change the turbo by much.

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