Originally Posted By: CATERHAM
And on track session are short; typically 20-25 minutes.
Then there are the popular Solo 1 time trials, which are actual racing but just against the clock. Track sessions are very short
comprising only four laps; one warm-up, two timed laps and a cool down lap. Good luck getting you oil up to temperature at those events. No one with half a brain runs heavy oil. 20 and 30 grade motor oils dominate with the knowledgeable racers.
I can tell you right now that I can get my oil temp up to 90C during the summer in less than 20 minutes. I'm sure this is the case for many other cars that are tracked. So while what you posit may be the case for your cars, it most certainly isn't for all of them.
A knowledgeable racer will run the oil that is best suited for his/her vehicle based on its requirements and behaviours. When I was drag racing my Mustang there were some very knowledgeable racers (guys with fast cars with a lot of money in them) that ran everything from 5w-30 right up to 20w-50. These were guys that tore their engines down every season and checked to see what worked and what didn't. Now of course drag racing isn't "tracking" in the same sense we are talking about. The runs are much shorter, foot to the floor, with pretty decent cool downs between runs. But that doesn't change the fact that
verifying what worked in a particular engine/car combo was what was being performed here. There was no blanket oil grade nor brand choice that applied.
And an interesting observation: A stock-blocked 302 making 3x the stock power level with what amounts to probably 1,000+ 1/4 mile passes under its belt still sits in my buddy's garage with what must be close to 400,000Km on it now. The heads have been "fixed" a few times due to some tuning issues (welded aluminum), and the engine was torn into about 6 years back due to it ingesting 15L of coolant when it popped an intake gasket on one run. He's run M1 5w-50, M1 15w-50 and Castrol Syntec 5w-50 in it pretty much the entire time I've known him. That would be at least 13 years now.
1. That engine has never "blown up" despite being flogged while still relatively cold at the race track with 5w-50/15w-50 in it, hitting 6K every shift right up to 120+mph.
2. That engine, when it was torn down for the coolant ingestion, was spotless. The cylinders still had visible cross hatching and the bearings were immaculate.
3. You'd be amazed how hot things get (including the oil) with the engine on for a couple of minutes when 10 seconds of that time is spent with your foot to the floor and you've got a big old supercharger that shares the engine oil helping with that.
Which brings me to my last point: I've never seen somebody blow up an engine drag racing due to "too heavy" an oil. I've seen bad tunes pop head gaskets, I've seen somebody toss a rod, I've seen a flywheel come through the hood of a Camaro; I've seen some very dramatic mechanical failures due to a part that just couldn't take the stress but I've never seen anything ever traced back to the oil they were using being too heavy. And I would think that given drag racing doesn't give you any "warm up laps" (just idling in the pits while you check and verify and perhaps some idling in pit lane) to put any sort of heat into the oil and that guys are icing their intakes between runs, that if running cold, thick oil was going to cause a failure, we'd see it here
About the only oil-related failure I can think of off the top of my head is with guys running the stock oil pump drive shaft on a 302 or 351 with an HV or HV/HP pump and a heavy oil. This has a tendency to licorice-stick the shaft or breaking it resulting in an immediate loss of oil pressure. Usually those guys catch it in time though. FRPP and ARP both make hardened replacement shafts that make it a null-issue, and those shafts are usually installed with the new pump, so the issue is not common. I've never seen it kill an engine. But I have
heard of it happening the states back when I used to be a regular on the Corral.
