Engine Oil Discussion

Charrlie_S said
No I don't do oil analysis, or dyno testing. As you say it can get expensive, and in my situation. not needed. I have only had two engine oil related failures in about 50 years. One was in my early days of slant six racing (cured by using full groove main bearings) and one was about 1 month ago, due to running the engine out of oil. (my own fault). I have done back to back drag strip runs with different viscosities of conventional oil. My 170 slant six engines turn between 6,000 and 7,000 rpm (depending on the engine) and have no problems. I have two vehicles I purchased new, back in the mid '80's still running fine. One has 412,000 with only a timing set change. The other has almost 200,000 and has never been opened up. I maintain, with the early engines (almost any make), if you keep the oil/filter changed, and the oil meets or exceeds API specs of SF (which almost any multi grade oil will do) Why waste money. I get my hair cut, I don't pay for a hair style.
All of that said, if you are running a "newer" type vehicle, or really extreme conditions, then yes, you need better.

Testing oil at the track is similar to testing oil on a dyno. The issue becomes the procedure used to do the testing.

You absolutely can not back to back oils, either at the track or on the dyno. You have to have a cleaning oil to run in between the reference oil and the test oil.

Oil remains in the engine in pretty significant quantities after you drain the pan. That residual oil skews the test results.

An example of this is when I gave some oil to be tested and they didn’t use a cleaning oil between oils and they made 3 pulls on the oil. You can’t do that.

What happens is the residual oil (and its additive package) is still in the engine when you change the oil. It takes 9 pulls (3 sets of 3 pulls) on the reference oil, 6 pulls on the cleaning oil (2 sets of 3 pulls) and 9 pulls on the test oil. That’s the ONLY way I know of to accurately test engine oils.

Is it worth it? Probably. But there are other things that synthetic oils do than just make a horsepower number. Like valve spring life. Cooler engine temperatures. You can use a thinner grade of oil (if you set your clearances up for it) and increase power and bearing life.