cwichert

Hi,

I tried to read as much as I could about topics on oil, but I am new to this world.

Bought my dream car this week, a Porsche 993 C2 from 1997 with an aftermarket twin turbo from Protomotive. Seems to have run so far on Valvoline VR1 Racing 20W 50 motor oil. Since on the way back to my home town one of the oil hoses from the turbo broke, I had to refill some oil, and I put some Mobil 1 15W 50 in, according to the recommendations of my Porsche expert dealer.

Now I wonder, if I actually mixed synthetic with conventional motor oil and if that was really a good idea for such a beauty piece of art of an air cooled engine...

Can anyone please advise what I should do and what oil to go for as of now?

Thanks
C.

Steve Weiner-Rennsport Systems

Hi,

Turbocharged engines really need a good synthetic and for a Mobil 1 product, I'd recommend V-Twin 20w-50 over the 15w-50 stuff.

nine9six

VR1 is a synthetic

Valvoline advanced synthetic, Valvoline™ Racing Synthetic (VR1)

20w50
API SM/SN
KV @ 100 = 20.0
KV @ 40 = 147
VI = 154
TBN = 8.5
Flash = 230 C
Pour = -36 C
CCS = 5000cP @ -30 C
MRV = 11000cP @ -35 C
NOACK = <15%
Zinc = 1400ppm
Phosphorous = 1300ppm
Calcium = 2100ppm
Sodium = 490ppm

If you don't know the last oil change and the oil used, Id do a fresh oil change if you just purchased a car and there is no documentation indicating last oil change and oil used.
If the aforementioned is the case, then both oil filters should be changed as well.

hacker-pschorr

It's both, gray bottle is non-synthetic:

http://www.valvoline.com/our-product...vr1-racing-oil
​​​​​​
Black is synthetic:

http://www.valvoline.com/our-product...etic-motor-oil

pp000830

Not to worry even if you topped off your oil with a little non-synthetic oil it doesn't matter for two related reasons. First oil labeled synthetic by the major brands is not synthetic it is made from petroleum base stock the same as non-synthetic. My understanding is that it is further refined to reduce the impurities that the additives need to keep in solution to avoid sludge and regulate viscosity. Your car holds well over 10 quarts of oil in its system adding an entire quart of non-synthetic oil is adding less than 10% to this total amount so any change to the properties of your oil fill is very small if measurable at all.

A far as what oil brand to use in the long run that is up to you. The only consensus you may get on the subject here is an oil with elevated ZDDP in it is probably desirable as it helps the durability of the valve train, however, using oils with extremely high ZDDP levels are not recommended by the manufacturer or the oil companies on cars with catalytic converters because it shortens the life of the converter. Then again some members here do it anyway.

Andy

nine9six

Well I'll be...looks like it is and it isn't.

I used to run VR1 in my 3.2's when it was on sale.

@ Hacker-Pschorr, thats one hellofa post count!

hacker-pschorr

I've used both off and on over the years, same here when it's on sale I stock up.

There is a 3rd version labelled "not for street use" which is supposedly a "true" racing oil without detergents.


Long winters......

cwichert

Thanks for such quick answers, I am impressed although I already heard before that this forum is run by very passionate and helpful people.
I can't express how rewarding it is to drive and listen to an air-cooled engine... unreal.

nine9six

The long winters come in handy if spent with the likes of your avatar...Very adorable cupcake!