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Please help! Dead 2nd turbo?


Bob

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  • 2 weeks later...

Tried the 5-minute TTC mod today (which seemed to make the exhaust embarassingly loud as well!).

 

Given that the car was hitting 5k rpm and struggling to get to 80 I'd say it's certain that no. 2 is a goner. I'm not also pretty sure that the fluttering / tinkling sound I can hear is bits of ceramic stuck in the exhaust system (no 1st decat) :(

 

On a positive note, hoping to pick up a 2nd hand set of turbos this weekend :) (thanks to Andyhannah :thumbs: )

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The auto box also seems to playing silly-buggers now; it's not changing down or up where normally it would.

 

 

good luck with the problem

just thought Id comment on the above as this may also be unexplainably linked to you issue

 

faulty speed delimiter/convertor MAY do this.

 

Rich:d

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  • 2 weeks later...

Car was running at stock boost, the only modification being an exhaust and 2nd decat :(

 

I'll be going single but not til the new year; thankfully I've got a 2nd-hand set to go on courtesy of Andyhannah :)

 

I'm quite chuffed so far, as I've managed to get the cat off as well as the turbo stays and oil pipework all with the hangover from hell. I even fell asleep under the car for about half an hour! Must say though, the Loctite 'Freeze & Release' stuff is an absolute godsend!

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Bob,

 

Your avatar shows a UKSpec - in that case exhaust and 2nd decat don't alter maximum boost.

...or is it a JSpec (like the signature says) with a bonnet scoop stuck on it?

 

Either way, have you got a boost gauge to verify that it was running stock boost? That would be disconcerting indeed...

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Chris and co,

 

I understand that obviously the J-spec tubbies are weaker than UK Spec. However, how do new hybrids compare with UK spec tubbies? Are the internals made of steal or are they still weaker in places?

 

I only ask because my new Envy ST3 hyrbids were fitted in May of this year and what to know the 'rough' life expectancy. I never intend to run anything above 1.2 bar, normally I only run *standard?* 1bar.

 

Thanks, Greg ;)

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I don't agree, I have FAR FAR FAR more trouble with UK spec turbos, they are not built to the same tolerances, go out of balance (wear) faster, and have oil smoke issues at low mileages. I find the J-Spec turbo engines perform better, last longer, and are FAR nicer to drive. Many may disagree with me :) I don't like hybrids, they don't work well, IMO, the exhaust housings are too small to balance well with much more air flow from the compressor side. having said that I fit quite a dew of them and the owners seem happy!

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Greg, your hybrids should take more than 1.2 bar, so will be fine at that setting.

 

J spec hybrids (stage 3's) have all the advantages of the UK spec & the J spec turbos, plus bigger compressor wheels!

 

They have the steel turbines in common with UK spec & the bigger diameter shafts from the J Spec (bigger bearings so can take more load & are less likely to snap!).

 

They will take a lot more boost than a J spec, and should deliver it more efficiently than a UK spec, although they will be more laggy than both.

 

An option to improve hybrids that I'm looking at is to have both the turbine & compressor extrude honed to improve gas flow & therefore spool up time and efficiency.

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Thanks Chris and Sup.

 

I'm quite surprised at that Chris. Just shows the difference of opinion between people and mechanics!

 

Thanks for enlightening me with the advantages of the hybrids Sup mate. Seems they offer good reliability, performance and spool for the money. Happy they were fitted now :)

 

So Chris as per Sups comments - will having both the turbine & compressor extrude honed improve gas flow & balance the air flow from the compressor side resulting in a faster and more efficent spool up time? ;)

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Try here Greg.

 

http://www.nissanperformancemag.com/april06/nerds/

 

http://www.nissanperformancemag.com/march02/projectser.shtml

 

It looks like its something worth looking into, and if it proves to be not a cost effective benefit then at least its been considered!

 

I'll be doing this at some point on a pair of rebuilt hybrids, and also back to back tests to verify if it has made a difference. I'll let you know how it goes.

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I don't agree, I have FAR FAR FAR more trouble with UK spec turbos, they are not built to the same tolerances, go out of balance (wear) faster, and have oil smoke issues at low mileages...

I guess I've got a 'goodun' then, peaks regularly at 1.5~1.6bar and couldn't exactly be described as 'low mileage'.

Not by a long shot.:D

 

Oil is fully synth changed every 1500-2000 miles though, and airfilter is stock.

They still haven't given up the ghost:innocent:

 

I agree about the hybrids ofcourse, they are mismatched and begging for compressor surge without tackling the exh A/R issue

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It's the same as the USSpec.

The americans believe that the shaft is a bit too thin for the sort of loads it has to cope with - There was a turbocharger designer/whatever on supraforums explaining the issue.

Maybe he was on to something.

 

In any case, I've found experimentally that obsessive/frequent oil changes can greatly prolong the life of a turbo that is running way out of it's limits.

 

People who stick to their manufacturer's intervals miss out, especially when running high boost. It's hard to prove though.

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If he's got those bits of ceramic in the firts cat he's got J-Spec tubos, I am sure it said ealier that it's a J-Spec car with a glued on scoop.

 

Sadly, that is the case. Not only that, but as far as I can tell it's superglue so any chance of a half-decent bonnet once I take the air-brake off (no hole either :rolleyes: ) is nil.

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. . . they don't mess about, do they?

 

Looks like #1 was a little worse for wear as well. These taken off at a smidge over 90k miles on the clock.

 

Thought you people would like to see some not-so-pretty pics :) ;)

 

image

 

image

 

image

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