Engine oil poll, track cars

[MVZ944T]

What kind of engine oil do you use in your track car?

How often do you change it?

How often do you change your filter?

[Ted Myrus]

I use Mobil 1 and change the oil and filter after every event. Oil is cheap. Have you noticed that gasoline is well over three dollars a gallon, but oil is about the same price its always been?

[MikeD]

Oil? I need oil?

Haha. Actually, I use Mobil 1, one or two grades thicker than what was recommended (for street driving) by the factory.

[Jad]

I use Mobil 1, 5 or 10/50 weight and change about every 2500 miles. I put about 1 quart in per big track day (two drivers) and with the street driving and AX's, 2500 miles means about every other TT it is changed.

[4est]

I use 50 weight AmsOil racing oil. It's the same price as Mobil 1, but better. My car runs noticably cooler (as read from the guage). Volker Brukkman suggests changing it every 20,000 miles on a street car. I was so impressed with it that I run it in my Land Rover Defender with similar results. When the warranty runs out on the Cayenne, I'll use it in there, too. After about 7500 miles in a 993 (used extensively on the track), it still looks new on the dipstick.

my $.02

[Jad]

I am not speaking about the Amsoil, but the job of an oil is to remove the gunk from the engine as well as lubricate. If it looks black and yucky, it is working well cleaning things. If it stays really clean, either it isn't cleaning or the engine has zero blowby or leakage, not likely on a track 993.

My understanding is that no modern oil will break down under normal conditions, they need to be replaced to replenish the cleanser and additives and to remove the gunk they pick up. That is why some people don't like good synthetics, as they claim they cause oil leaks. What they really do is clean better than regular oil and can clean clogs out of small leaks, making them bigger. Also, time hurts oil, so regardless of mileage, an annual oil change is needed.

Of course, oil is a black science, so opinions will vary

[JamesWilson]

We utilize Oil Analysis from Blackstone Laboratories in Indiana (www.blackstone-labs.com)....free containters, just take an oil sample through the dipstick or during an oil change, mail off the sample in the container and fill the form out, and you are sent a complete analysis based on wear metals, contaminates, oil viscosity and other specifications. Like $20 and you get the report back within a week.

I used to run Royal Purple Racing 51 (like a 20w-50) in the 924 Turbo, oil analysis showed low wear numbers and despite a little extra fuel dilusion, it remaind a 50-wt oil (did not shear out of grade) even with the hot turbo.

I am now running a blend of Valvoline VR1 Race Oil in 20w-50 (non-synthetic) and Royal Purple 20w-50 (non-race formula), haven't done an oil analysis yet. I will probably switch back to either the RP Racing 51 or RedLine 20w-50, as it is easily accessible. Mobil 1 15w-50 is another excellent choice for most p-cars, as is their old Delvac 1 5w-40 (now called "Truck and SUV 5w-40")....an HDEO with more phosphorous and zinc/zddp as anti-wear agents, but has the potential to poison catalytic converters in cars that tend to consume oil or smoke. Guys have been using the LubroMoly oils for some time with good results, have not seen a UOA to back it up though.

Every engine is different. Black or dirty oil doesn't necessarily mean the oil is "done", only analysis can show that. If you do have oil that smells like gasoline or contains coolant, change it out and find/fix the problem.

[John Straub]

I use Mobil 1.

[Dan Chambers]

LiquiMoly 20-60 is my blend, with a little Valvoline Racing-1 50 wt. or Royal Purple mixed in.

The cost to use is equal to or slightly less than Mobil 1, and my engine runs slightly cooler with LiquiMoly. I also notice that instead of 1/2 qt. burned during 2-day TT's it's more like 1/4 to 1/8th per two-day TT.

I change out my oil every 2000 miles if tracking AX's alot, and always change it out directly after a TT (especially since I drive to and from the TT tracks on the street. This ain't no trailer queen ).

I like the Liquimoly, and blend it occassionally with Royal Purple.

[harnishclan]

Why use 5W oil in SOCAL? The viscosity would never get down that far with our climate. 10W is designed to go as low as -10 degrees. Flip side is why 50 weight? The higher viscosity will increase oil pressure and decrease flow. Newer engines have tighter bearing clearances than older ones and forcing a thicker oil through could cause problems, not to mention robbing horsepower. If you are changing oil for every track event, makes sense to go with the lowest viscosity that gets the job safely done. You would not take away horsepower needlessly, pressure and flow througout the motor would improve, and the oil is not going to become saturated with suspended particles and break down because you are changing frequently.
All that said, I use Mobil1 changing the 993 oil every 6K, 944 every 3 months, Cayenne haven't had long enough, 924T hasn't run long enough to need an oil change yet!

[Jad]

Brian, I basically agree, but isn't that the point of a multi-grade oil, it flows over a wide range of temperatures? They flow freeley when cold, 10w, (thus they also flow freely in SOCAL temps) and stay viscous when hot, like a 50W. I would not use a 10W or a 50W, but a 10-50 should be fine, right? No loss of HP from being too thick before getting hot and plenty of safety for cold mornings. I used to use Castrol 20W-50, but Mobil 1 synthetics only come in 5-50 and 10-50. And after the last Big Willow event, I was glad I did have that oil. I think it was about 12F when I barely started the car with a tiny Optima battery.

[martinreinhardt]

Personally, I only use Mobil 1 because that is what Porsche uses these days. In Europe I used SuperSync 0W40 and here I use SuperSync 15W50. I replace the oil and oil filter every 5000-10000 miles on the 911 and every 15k on the Boxster.

[Dan Chambers]

Brian: Pretty much what others said regarding viscosity. The higher vis. keeps the pressure up and the cooling capacity up when driving hard on high-temp big tracks. The low-end vis. allows for cold-morning starts and no loss of HP - or reduced oil flow at cooler temps.

I think the synth. multi-vis oil is the way to go, especially when driving hard/competing. I gave up single-viscosity oil about the time I stopped parting my hair .

~(:^)>

[bibbetson]

I've been using Maxima Racing Oil (www.maximausa.com) for about three years. I only use their Maxum4 Ultra product which is 100% synthetic and developed for racing. Initially, when I was the only driver of the car and only drove autocrosses, I ran 0w10/5w20 (it's labeled 0w10 but measures more like 5w20). I know, that's really light oil, but I tried it on a recommendation from their blender as I always had bad valve train noise on startup using Mobil1. The first time I used it the noise was gone and it has never been back even on the coldest of mornings. I have also used their 75w90 synthetic gear oil for the past two year and have been very happy.

This year I switched to a new blend 5w30 to improve heat stability in hot weather. Using the 5w30 solved a drop in oil pressure that I experienced on a really hot summer day at a two driver DE. They have some NASCAR teams using this same oil this year as well.

Maxima is one of the top oils in the off-road and water sport arena. They have been slowly moving into the 4-cycle world recently. They are a local company (Santee, CA.) that custom blends their products using the best base oils and additives available. Because they aren't making millions of gallons, they can use more of the good stuff, as appropriate, in their oil.

I change my oil before every Time Trial or every six months with a new filter, regardless of miles.

(My brother-in-law is the oil blender for Maxima, but I wouldn't recommend their products if I wasn't happy with them myself.)

[John Straub]

Bill,

Do you have a phone number for them?