Turbo Miata burns quart of oil a day, what do you think?
 

Hello this is Josh,

I've got a turbo 99' Miata with a serious issue that I need to verify. My motor burns through a quart of oil in a day (8 hours) of driving it. It has no leaks. The turbo is one month old, it is a GT2560r w/ an oil restrictor. The cylinder head & cylinder head gasket were refurbished w/ all valve stem seals 4 months ago. It is currently running on E85 and 14.5 psi. The motor was rebuilt stock back in 2018, and it has about 45,000 miles on it. 10,000 of those miles were boosted. The motor will make a massive ploom/cloud of blue smoke on cold start for about 30 seconds. It will continue to make obnoxious plooms of blue smoke through heavy boost loads and especially during decel (like downhill). Also, both ports on the valve cover are connected to the oil catch can and is ventilated into the intake side of the turbo. It pulls ALOT of oil from the valve cover, where the oil drain on the catch can is dumped straight to the ground.

Before I go rebuilding another motor, I just want to be extra sure it is oil rings. If you have any experience with serious oil burning, please let me know. I know its my oil control rings, but can you validate my concerns?

i plumbed my catch back into the sump.
blue smoke on end of boost = restrictor or turbo seals

engine could be fine. leakdown

plumb into sump is a good idea. Ill get back to this thread on the leakdown.

Did you use OEM valve stem seals or like Supertechs? Generally Supertech is a trusted brand for parts here, but for valve stem seals - the tolerance is too loose. When I built my engine with Supertech valve seals, I was burning about a quart every 2 tanks. I thought it was a bad build or rings. When I replaced them with OEM, oil consumption went away.

It's been discussed on these forums a bit but took quite a few years for most with engine work to narrow down the ST seals as the common denominator.