Any blown Greddy turbo's
 

Hi, I don't own a 350z, but hoped you guys could help me out. I own a turbo'd Rx8 with a greddy kit using a TD06-18g turbo. Alot of the 8 owners have been blowing this turbo, myself included. I was only running 5psi and only had it installed for 1500miles. There are many other similar cases.

I'm getting ready to reinstall myne which was rebuilt, but am still trying to find the cause of failure. I doubt its the turbo itself since Mitsubishi guys have been running them for a long time without problems, so it must be something with the way Greddy sets up the kit.

I was wondering if any 350z owners are having problems with the turbo failing? Also, wondering where Greddy taps your wastegate line. On my kit its tapped at the intake manifold and that's suspected to be the problem. I think it needs to be tapped before the throttle body so the turbo isn't trying to cram 7pounds of boost into the manifold at 30% throttle. And yes, with this turbo on the 8 you can make full boost at 30%throttle. Gets kind of annoying during regular take offs.

Do you have a bypass or blow off valve...if not you are most likely surging the turbo into death...

Yes I do have a bov. There was one day when I was checking for boost leaks and fooling around with things that I overtightened it and drove around with surge for a couple of hours. But, I readjusted it the next morning and haven't had any since. I didn't think it would be a problem since the kit didn't even supply one and Greddy claimed it was good to have but not essential.

There have been a few reports of turbo failure, but given the large number of greddy kits installed, it doesnt seem to be a trend. As Mia suggested, are you running a BOV?

Your turbo failure has nothing to do with where the signal line is tapped...pre or post throttle body.

i had some turbo problems, but that was b/c the passenger side turbo's oil return line pinched and backed the oil up into the turbo. this in turn broke selas and damaged the turbo.


i know a few guys in houston with the greddy kit on their rx-8 and ive never heard of their turbos blowing

The reason I suspect the wastegate signal location as being the culprit is that when at partial throttle the throttle body will act as a significant restriction, so it'll having a large pressure differential from one side to the other. If you're at 30% throttle making 7psi in the manifold, then you may have a great deal more at the turbo compressor outlet. So you could be constantly overspeeding the turbo. Also, since you may have such high pressures and such little flow you could be operating it very close to surge.