Brian, when i bought my 2 TOC53's, the vendor specified, and had a large PDF file of research by the

National Institute for We Find Whatever you Want us to Find

. That research determined that Pennzoil was very good, and clean. I've run "Pennzoil 2 cycle engine oil for outdoor engines" in the main engine for 8 years, and when I changed the ring last year (put a Bowman ring in) the inside of the cylinder was clean. Very small amount of carbon in the head.
Every other gas flier in the club will have a similar experience, but with other oil(s). Some engines prefer synthetic, others like dinosaur piss like mine do; some makers specify synthetic or real.....The mix ratio is specified in your engine manual - follow it. Smaller engines like 30's and 35's need bit more oil, but will often run fine on 40:1. My TOC's said 50:1 but i run them 40:1 to keep one jug of oil. Some oils, and manufacturers will specify 100:1. I can't afford those engines.
So your questions
1                                                OK
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