[MA70-3.0GT]

Just another angle on the engine bay smoking & oil loss... It's a Turbo right? How's the turbo feed/return unions doing for leakage? Don't think the 2 lower ones on the block would hit the 'zorst but I know from bitter experience that the one where the feed/return bolts up under the turbo drops lube so that it hits the downpipe when you're on the move (this can be accompanied by a puddle of lube on the floor under the car too, if it's not all getting burnt off).

I was losing a fair old amount to that leak (so badly was it covering the downpipe and smoking up, I made a temporary shield in case it caused a fire!) and was about to bite the bullet & pull the turbo out AGAIN to replace that 10p paper gasket when I got splatted by the BMW driver.

Just a thought & it's well worth actually checking the I/C as described a few months after cleaning, before pulling the motor in case the loss is purely external. It's sometimes surprising how much is pouring out of a motor without making an appreciable stain on the driveway.