We race the car, thus we change oil every other race weekend. Changed oil like ~20 times this year, so the oil does not matter when racing. Pennzoil or Mobile 1 as long it is 0W-40.
I change my oil about every 1000-1500 miles, when it starts getting black on the stick I drop it. I also cut the oil filters open and check the pleats, a oil filter cutter makes it to easy to not too. The filter media in these filters is almost 6 ft long when pulled out!! I run my car hard, it doesn’t get babied. I buy all my oil for all my other cars at Walmart including Mobil 1 15w50 high ZDDP oil that I use in my solid lifter 69 302 block, can’t beat the price for 5 qts. And I’ve eye balled the 0w40 Euro spec many times and thought about using it in my cat since I change the oil 3-4 times a year in it. I may give it a whirl next change especially now running 85% ethanol after seeing that oil report, THANKS for posting.
Speaking of Ethanol, get this. I run a UPR remote mount catch can, I’ve found the UPR design to be the best in my opinion at getting everything out of the PCV stream. I’ve had my blower opened up a few times and with the UPR it is absolutely spotless inside, with others their was oil residue. BUT I’ve found it REALLY separates EVERYTHING out of the PCV stream. Since it has gotten colder here in Pa I found about a1/2” of crystal clear liquid in the UPR. It also had 2-3 pea size perfectly round yellowish oil beads floating in it, thought it was water at first. Guess what it was? 100% pure Alcohol!!! Seems the cold remote mounted UPR even condenses the alcohol blow by out of the PVC stream!! Any one else ever notice this running corn?? When running gasoline I used to have a very thin oily residue in the can snd it had a gasoline smell to it as the oil aged and I’d change the oil when it started to smell like gasoline. I check my cans contents often, finding the crystal clear liquid surprised me. I tested it with my tester and it tested as 100 % alcohol, burns invisible clear with just blue tips on the flames.