timrxmotors

It is possible that the one apex seal I did break caused some damage to the turbine,but there were lots of bits embedded in both rotors,which seem to have entered through the exhaust port,as that was where the scoring was.Point is since then more bits entered the engine,and more of the turbine wheel has gone,with nothing gone through it apart from the bits from the melting turbine wheel.
My turbo man agrees without doubt it has been melting.

Zero R

iTrader: (1)

GT42R's are fine on rotaries, I know plenty of people using them. The pictures shown aren't the best, but that looks a lot more like apex seal damage.

crispeed

It seems like apex seal damage to me also. Seals don't only break from detonation. Too high egt's would warped them and also continued use at that tune leads to excessive seal growth and then breakage.

Boostn7

Well...when seals break they will get crushed between the rotor and housing 'till making out of the exhaust port into the turbine housing. In the cone of the turbine housing bigger debris gets trapped coming into contact with the inducer of the turbine wheel causing the exact damage you have...bent/missing tips.
The turbine exducer show no signs of melting.

I've seen people replace a broken motor to end up with another broken motor...becuase they never bothered to check for remaining broken seals in the manifold/turbine/wastegate area.
During start up or shut down debris drops in since most manifolds sit the turbo higher then the exhaust ports.

Gool luck.

timrxmotors

Picture of the turbo.I understand it has a TA51 turbine wheel and housing.Is this the one you have on your car? How does it compare to a GT42 turbine housing?

Zero R

iTrader: (1)

The turbine housing is a T6 like yours but mine has a 5" v-band connection, the one on the right.

timrxmotors

I need the turbine housing like yours.It seems the one I have is too restrictive where the gases enter to the turbine wheel.That is how I have 10 psi exhaust pressure,running with no turbo core.The pressure will greatly increase the temp of the gases onto the turbine wheel,higher than what I see on my egt guage.
Obviously yours works fine,so how much for a turbine housing?

timrxmotors

It is bits from the turbo,because they are not magnetic,whereas the apex seals are.

timrxmotors

I spoke with another turbo man today.He says the turbine wheel on my GT42/51R is not inconel,but made from a material called GMR.
That means it can withstand 850c sustained,I've seen that on cruising,no wonder it is melting!
Also,the turbine housing is a split pulse type,one side of the divide is smaller than the other,great on trucks for better spool and low down torque,but if you have a divided manifold on a rotary,one rotor will have higher exhaust pressure than the other.
Maybe I should fit a large diesel engine.
He recommended a GT35/42R,sounds interesting.

Zero R

iTrader: (1)

Certain feromagnetic metals iron, steel etc. when they are heated past their curie temperature will lose their magnetic ability.The atoms become too excited by the heat to remain pointing in the same direction for long. Don't know what the curie temp is of the apex seals but it is something to consider. A 35/42 is a bad idea through and through. You'll be running too small a turbine wheel for to large a compressor. Just get a GT42R not some half this half that and you will be fine.

Jim Swantko

Anyone ever seen a non-divided housing for a 42R? I've been looking but can't find one.

crispeed

There are also the GTS line of turbos from Precision if you're looking for something very close to a GT-42 in a smaller package and makes just about the same power on a 2-rotor up to about 650 to 700rwhp. The GTS turbine wheel is very close to the 42 in dimensions and design and come packaged in a .81 or .96 style T-4 turbine housing. Many compressor combinations are possible with the most common wheels being the 71, 74 and 76mm. Toyota 2JZ-GTE's are making well over 900rwhp with that turbo with quicker spool up than the Greddy T-88's.

Zero R

iTrader: (1)

I'm working on getting some made as we speak. It may be awhile. It took me forever to get the T4's made for the 35R. What are you going to use it on?

SPOautos

Just looks like typical apex seal damage to me. Also if it was melted you should have much more discoloration. That just looks like standard damage from engine internals going out the exhaust and hitting the turbing wheel.

Stephen

bobybeach

hey guys! masterpower gt45, same spec to the garrett gt42 and uses t4 flange with 4" v dand for easier fitment

Jim Swantko

It will be on a modded GT42R76 (the 76 is now a little bigger than a 76) - it will be sitting on top of a Full Race manifold... how much would a 1.01 A/R undivided T4 housing cost me?

BTW - I have a PTE 76 GTS for sale if anyone is looking - it made 860 rwhp at around 32 psi. Spools very quick for that type of power IMO.

Zero R

iTrader: (1)

Please Jim, tell me you didn't buy the full race manifold. I have yet to see one fit. I can get you a much nicer manifold if your interested probably for less. Won't require water pump modifications, equal length tapered long runners. As for the undivided I'm still waiting to hear back from them. But I was referring to T6 footprint as well.

Jim Swantko

I got a good deal on the manifold since I'm going to be doing some testing on my car with it.

I'll let you know if there are any fitment problems when I put it on... but MSP has their headers (T6) on both of their cars. Mine is a T4 flanged setup and should clear the GT42 no problem. I better not have any problems fitting that manifold on my car - or it WILL be going back!