SC using a lot of oil

[KingSalmon]

I just bought a 78 SC Targa for my first ever Porsche. This car runs great, looks great, and it is a blast learning how to drive it. It is stock except the Carrara Valve covers. 147000 miles. My biggest problem at the moment is it uses a lot of oil. Approximately 1 qt every 350 miles. It leaks a little and does not smoke at all. I do smell burnt oil in the garage after a drive or when I turn on the heater.
What it is leaking on the ground might add up to 1/2 qt in a 1000 miles.

Any ideas where the oil is going ? Could it be leaking onto a hot manafold and burning without hitting the ground ? I don't notice smoke coming out of the motor compartment.

The PO told me to put Valvoline 20/50 in it. I've been reading on this web site a lot and I think my car is the only one in the world using Valvoline.

I am due to change the oil pretty soon. Using this much I don't really want to use expensive oil. What do you guys recommend I use.

Thanks

[Doug Steinel]

I ise 20W50 in the summer..Valvoilne, Pennzoil, any of the majors. My '82 SC engine goes through 1 qt every 450 miles. The higher viscosity oil leaks more slowly and less is burned, In the winter I change to 10W40. In these high milage engines, I imagine some is going by the rings and some the value guides. You could do a leakdown test and find out where much of the wear is.

[Bill Douglas]

The Valveoline 20 50 is good stuff, so use that or alternate to something else with the same viscosity every other oil change.

Fill it up to a bit over the low mark, and the oil level should be read on the dipstick when the car is well warmed up and has then been left to idle for a minute.

My '79 uses oil if I fill it to full. Gawd knows where it goes, and once it's down to the quarter mark it stays there and only needs a quart between oil changes.

[Neilk]

Just wondering, but do you check the oil level while the engine is running and at operating temperature? If not, you won't get an accurate reading and may be putting too much oil in the engine.