Red-Rx7

Ok.

My turbo has 1700 miles on. Everything was great, until midway to the RR. I started noticing quite a bit of oil in the exhaust during backpressure (i.e. letting of the throttle).

At first, everyone thought it was just a tuning issue, for I have yet to tune the car for cruising. At crusing, under vacuum, the AFR is around 11.4:1. So, the car shoots 6 feet flames.

Well, during the trip I started to notice some loss in power. It is hard to tell, for the car still went sideways at 90mph on dry ground. But, I was trying to figure out if it was me just getting "use" to the power which felt less of a "WOW", or it was really loosng power.

Anyways, after the Rotary Revolution on the way home, we were cruising along and I went to pass someone. I was in 5th gear, and always able to build full boost (i.e. 26 psi if needed) by 2800 rpms. This time, during the pass at 25% throttle, it wouldn't develop positive boost pressure.

We pulled over, and noticed the turbo wouldn't even spin at idle (it is a dual ballbearing, use to spin for 2 minutes, 30 seconds after the car was off).

Having no choice, we got back on the road and I treated it like a baby most of the way home. I was pretty pissed off, and the car would make boost (only about 8 psi) by near 6000 rpm. That is a crap load of CFM on my car, to just make 8psi. Even though it made 8 psi, it was way down on power, but still enough to go sideways .

Now, looking at the turbo, it has enough shaft play to drive either top (when pushed up) to rub the housing (actually, it grinded a little edge off all the blades, and groved the housing) and the same on the bottom.



Ideas to what caused this? I have changed the oil every 500 miles, have it jetted properly according to the manufacturer. I have spoke to them, and they seem good to their word. They said they would tear it apart and take care of me.

Marcel Burkett

Do you have an exhaust pyro. ?, maybe you are running too hot and mansged to burn out tha rear oil seal ?

Red-Rx7

My EGT gauge doesnt' work, for I don't have the sender. Left it with the old downpipe / engine.

Interesting though. If my timing is "average", and the AFR is about 11.(2)-to-(4) : 1, what would make it run so hot to cause this?

Red-Rx7

bump

Gargamel

Sounds like the turbo might not be getting enough oil. Might want to talk to MVA about a warranty. What turbo do you have, Garrett?

I guess someones trying to tell you to get that bigger turbo you've been talking about.

RacerXtreme7

iTrader: (2)

oil jetted ?? You mean your running a restrictor on your turbo's inlet oil line? You say its ball bearing.... if its a Garrett GT series ball bearing turbo, their internally restricted and you shouldn't need to run a restrictor in the oil supply line. Perhaps staved it?

~Mike...........

jdhuegel1

Exactly what I was thinking. It sounds like it was starved. I hear it was common in a few Garrett turbos, due to the internal restriction. However, I don't have anything to back that up.. just hear say.

Red-Rx7

No, this is an Innovative, not cartridged jetted. So, we used NOS jets to restrict the flow to the turbo.

Gargamel

Innovative......... interesting. The only thing I can see wrong is an oil problem.

Call them up.