Oil Consumption & Quality

[turbotwig]

The real question is why do you feel the need to run 20-50 in a street car engine? That is probably a significant factor in your smoking issue. You'ld be extremely hard pressed to get the oil to come up to temp (and down to the correct pressure) with 20-50 in regular street driving. Sure, use it on the track, but it's pretty well pointless to do that on the street. I'd use whatever grade oil that Toyota recommends, and then use synthetic rather than petroleum based.

Don't forget the smallest part of your oil feed line (the fitting) is the 'restrictor size', not the hose size.

You should pull off the turbo end housings and see if you're getting and oil in them. If you can't find it in the end housings, then it's probably not the turbo at all.

Turbos aren't 'diesel' or 'gasoline' turbos. Depending on the application, various wheel and housing matierials will be used to deal with EGTs and mecahnical stress. So don't kid yourself, any way you cut it, the GT40 was originally designed to be a "diesel semi-truck" turbo. There are definitely no GT40s on OE passenger cars. :approve:

-Kirk

 

[Toysrme]

The differance of the example isn't in the turbo, but in it's application. It's a relative type of discussion.
Big diesel turbo's are designed to last 1/2 - 1 million miles.
They blow their seals relatively quickly against that mileage, they have huge oil supply & drain lines - but it doesn't matter that they blow their seals long before they're ever rebuilt. Nobody *really* cares on a semi-truck if there is some minor oil-loss, and billowing black/blue smoke every time you're on boost!

Bet ya didn't think of it that way hehehehe! :smileysex



That, relative to a car engine - you can't afford the oil loss, you can't afford the smoke, and you can't afford the build-up in the engine / intake over such a long period of time.
:beerchug: All things are relative!