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-   -   turbo damage from excessive heat, t04z (https://www.rx7club.com/single-turbo-rx-7s-23/turbo-damage-excessive-heat-t04z-930474/)

Bitchn7 11-12-10 11:27 AM

turbo damage from excessive heat, t04z
 
i have at04z that isnt that old, hasnt been hammered that much and has damage from excessive heat. apparently th exhaust housing has moved and touched exhuast wheel
can still be used but will get worse. particularly as we dont know whats caused the excessive heat. xcar is rich if anyhting.
was told this is common wiht rotaries, specialy circuit racers but i have never hear this befor so wouldnt have thought it that common.
Anyone else had thi sproblem?

housing shows sights on flaking in inside edge where exhaust system attaches

Turblown 11-12-10 11:59 AM

Where did you get the turbo from? Some people sell " garrett " housings that are knock offs. Its only common when running too retarded ignition timing.

CarbonR1 11-12-10 11:05 PM

Post a picture of the damage and the turbine housing.

crazyboosta 11-13-10 06:19 PM

Mate has had his trouble on his race car, turns out the Z have poor material in exh housing that warp from excessive heat making it touching rear wheel. Apparently GT series have better material in exh housing so withstand heat better, he's upgraded to GT3788R - so far so good...

thewird 11-13-10 11:35 PM

Are you running a turbo blanket? I had that had that happen to my 500R-SP after running it a season at the track with a turbo blanket. Although it wasn't from the turbine every touching the housings, just the heat flaked away at it.

thewird

Bitchn7 11-14-10 12:03 AM

this is a genuine garrett T04Z as bought from local Garrett distributor.
I did have a blanket on the turbo for a short while but has a small fire from coolant leak (small as in the flame was about the size of a lighter flame before i put it out).
Turbo has done a bout 5-600km after a base tune, then a full tune, maybe a few 1000s km of road use and a couple of day at the drags running no more than 18psi and only about 8 runs befor this happened.
should have turbo back tommorrow so will take pics
tune was quite rich under load and pretty tame timing from my understanding, will check numbers later.
considering tial exhaust housing when i replace turbo but dont think they do the a/r ratio i want.

crazy booster, how much of an 'upgrade' other than housing material is the 3788?

rx72c 11-14-10 12:07 AM

Its actually GARRETT that are using cheap shitty cast. The knock offs are alot better. Much thicker casting etc on the knock offs.

Turblown 11-14-10 12:27 AM


Originally Posted by crazyboosta (Post 10318207)
Mate has had his trouble on his race car, turns out the Z have poor material in exh housing that warp from excessive heat making it touching rear wheel. Apparently GT series have better material in exh housing so withstand heat better, he's upgraded to GT3788R - so far so good...

Z just uses a standard P trim turbine housing, common for most 90s eras turbos. I have only seen the flaking on cars running turbo blankets or way too retarded ignition timing, regardless of AFR. I am talking EGTs past 2000F pre turbo. Turbo blankets should only be run on diesel turbochargers. This is why we use inconel turbine housing shields with an air gap for proper expansion and contraction of the turbine housing.

crazyboosta 11-14-10 12:56 AM

Bitchn I dont know specifics but they are meant to be better LOL

Turboblown he never ran a blanket, its a BP running E85 making ~400rwkw with a good race tune, not some pie in the sky dyno queen tune for numbers. Exh temps were 1000°C + pre turbo but now with 4" exhaust and dump sees ~950ish °C I think he said GT series have a higher nickle content in their housings to help handle heat, will link him to thread and he can explain it's his car after all LOL

heres youtube vid of tune
http://www.youtube.com/watch?v=TQHTf9GPwLc

silverfdturbo6port 11-14-10 04:53 AM

On my precision i ran it pretty good with 23psi and a turbo blanket and it never had issues. I know that they are based on garrett but not sure about the exhaust casting?

jetlude 11-14-10 11:42 AM


Originally Posted by Bitchn7 (Post 10316367)
i have at04z that isnt that old, hasnt been hammered that much and has damage from excessive heat. apparently th exhaust housing has moved and touched exhuast wheel
can still be used but will get worse. particularly as we dont know whats caused the excessive heat. xcar is rich if anyhting.
was told this is common wiht rotaries, specialy circuit racers but i have never hear this befor so wouldnt have thought it that common.
Anyone else had thi sproblem?

housing shows sights on flaking in inside edge where exhaust system attaches

Did you notice any signs of damage to the turbine wheel from the heat? I have had damage to genuine garrett turbine wheels(blade tips melting) in the past from heat, but never to the housing. Check the wheel closely.

Bitchn7 11-14-10 09:24 PM

i havnt seen the turbo yet but shop i bought it from said only damage they saw was where wheel has touched the outlet of the exhauts housing (though they only cleaned it up around the contact area).
They are saying the temp (for what ever reason caused the hight temp)has allowed the housing to warp, possibly with help from the weight of the exhaust system pulling on it but our exhaust is mounted right up to the gearbox area at 3 places from the very rear of the car.

I serisouly cant believe i have heard so many people jump up and down how great theTO4Z is without hearing of this before lol but now im hearing it when mine fucks out, i hate that lol

CBR 11-16-10 02:47 AM

I'd be looking at the tune and the exhaust manifold.

Bitchn7 11-16-10 04:24 AM

lol, if you had in the first place..........................., but you couldnt be bothered.

as for manifold, i have seen far far worse that what I have.

kenn_chan 11-17-10 02:23 AM

Genuine TO4Z kit from HKS, HKS FCOn SZ making 430 RWHP at 1.2 bar 8000km's and no warpage, this includes a couple of wangan runs, several trips up and down hakone and the ashinoko skyline plus a lot of daily driving, no warpage, nor blade contact though it does smoke more than any turbo I have had in the past. (yes I have the HKS restrictor pill in it)

kenn

CBR 11-17-10 02:54 AM

when I say manifold I just mean that the flange has to be flat and not pull on the housing flange.maybe somthing stupid like condensation causing it to rust,tha cast would soak up water pretty wel and once heated maybe cause it to heat maybe,bit like the elements on a gas bbq that gets left in the rain:lol:they go all flaky

Speed of light 11-17-10 02:04 PM


Originally Posted by CBR (Post 10321791)
I'd be looking at the tune.....

I'd tend to agree with this. High temps and excess air (free oxygen) will contribute to a high erosion rate. It's actually burning the casting material--think cutting torch effect. Mitigate one or both of these factors and you'll likely reduce or eliminate the problem.

Bitchn7 11-19-10 12:22 PM

manifold flange was flat before, not so sure now. wasnt any corrosion on manifold flange when turbo removed. going to pull the whole lot off againg after this weekend, get manifold flange machined flat to be sure.
checking tune today and putting e85 tune in also

SHPNOUT 12-07-10 04:05 PM

Just found out my Garrett housing is warped as well. T4 devided .84. And I was running a blanket. This next evolution will be a shield. This is a dedicated road race car.

PandazRx-7 12-07-10 06:41 PM


Originally Posted by SHPNOUT (Post 10355581)
Just found out my Garrett housing is warped as well. T4 devided .84. And I was running a blanket. This next evolution will be a shield. This is a dedicated road race car.

Shield is the way to go it sounds like, I made a carbon fiber sheet as a shield with DEI Reflect-A-GOLD on the bottom/side... 300F+ difference between the bottom and top of the shield taken with my IR temp gun after 10 hard laps! I also use that stuff on the frame rails after the silver stuff burned and flaked off near the turbo...

Turblown 12-07-10 11:24 PM


Originally Posted by SHPNOUT (Post 10355581)
Just found out my Garrett housing is warped as well. T4 devided .84. And I was running a blanket. This next evolution will be a shield. This is a dedicated road race car.

http://www.turblown.net/store/index.php?productID=62

PDF 12-08-10 01:10 AM

Comp Turbo cast their own high nickel turbine housings to fit Garrett turbos + they do a good range of discharge v band flanges.

SHPNOUT 12-19-10 12:57 PM


Originally Posted by Turblown (Post 10356321)

You buying?

Fritz Flynn 12-19-10 01:54 PM

My last turbo housing warped and it was a genuine kit w/ a heat shield no blanket.

Probably around 6k track miles.

Just another one of those instances when you could of had a v8 :lol:

Turblown 12-19-10 03:14 PM

Last weekend at the track, a customer of ours smoked his turbo running a turbo blanket too. Took it apart, burnt the mobil 1 oil. The ball bearings, and case were all black...


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