sleder

I'm a conversion, that's right I converted from the all mighty 3.2 to the even mightier 3.6. I will be doing DE's plus whatever else I can find the time and money for. My question is which oil should I run in it. It's not a street car, and it gets trailered to the track. The oil will be changed every 1500 to 2000 miles. So, what do you recommend, and why?
Thanks for the responses in advance.

Garibaldi

I would run straight 40 weight. That is what we use in the motors I build. I bet you 25 cents that this post will thread out with people recommending everything under the sun, especially synthetic. SO do what you want, but straight weight- not multi viscocity, is what I use. No problems. Castrol 40 weight.

Garibaldi

Oh, and without getting in too deep, the syntetics cannot hold up in high unit loading, and multi viscocities are laoded with parafins that swell and a bunch of additive packages are in both which is not neccessary in that type of motor. Run the straight weight, let it warm up and get some heat into it, and it will be fine.

sleder

Thanks, That makes sense.

RedlineMan

Hmmmm...

I am not a blind follower of anyone, but I note that Porsche uses mutli-vis in everything. Mobil 1 - 0w seems to keep Cup Cars, RSRs, GT1s, etc. happy.

Me? Mobil 1 15w50. 150k miles strong. 1/2 pint per day expended. 70psi at any given MPH. 20PSI at idle crackling hot in the pits. For what it's worth.

YRMV.

sleder

Fair enough. Thanks!

DJF1

I agree... I use Mobil 1 15-50 religiously.... My car is happy on the track in the Houston summer heat. Just my .02

M758

For 944 applications I ran mobil 1 15w50. I would notice a oil pressure drop under track conditions to about 2.8 to 3 bar at high RPM.

I switch to Amsoil 20w50 Series 2000 Racing and now have oil pressure maintaining to 3.8 to 4 bar in racing conditions.

944 engines are prone to #2 rod bearing failures and anything that can maintain oil pressure and therefore viscosity under temp is good for the rod bearings.

just my experience.

Garibaldi

See, I told you that there would be varying responses. The truth is, that all of your multi viscocity oils, well any oil for that matter, synthetic or not can break down under severs thermal loads. The oil inside the case at temperature and under load is about as thin as water, maybe thinner, and the temp after its been circulated through the crank, rods and heads is astronomical.

sleder

Yes, however it should be making us think, and consider all the information that everyone is posting. This is great stuff!

Garibaldi

You should read the latest SAE paper on synthetics. And to comment on Redline mans post, is the Mobil-1 what you have seen them filling the motors with in the pits and during the race of any of those cars, or is that just what the sponsorship logo reads across the car?

sleder

Interesting, Where would I find theSAE papers on the oils in question?

APKhaos

Mr Garabaldi is right on the money! Local racer & crew who ran the Speedvision Challenge series on the ALMS circuit tell of comparing torn down race motors which had run Mobil 1 vs dino oils. The synthetic lubed engines had a nasty black deposit burned into the pistons and other less pleasant features.

For less stressful road duty, stick with the oil type and grade that Porsche selected when they designed your engine. Oilways and bearing clearances in engines designed for dino oil are different to those in engines designed for synthetics.

I know this topic draws opinions across the board, but the consistent voice of experience [not mine BTW - just the messenger here] is stick with high quality dino oil in early engines, and use appropriate type race grade oil in the track.

Flying Finn

Mobil 1 15-50

Garibaldi

One other suggestion I would like to make is that I would change the oil more often than you are plaaning to at 1500-2K intervals if you are going to be solely running the car on the track. Id do it every event.