Synthetic vs Blend

I recall buying Red Max and K&B fuel with synthetic oil when I started in the mid 70's. I have old magazines dated in the 60's discussing synthetic oils. Thats a lot longer than 20 years.

Maybe your Powermaster was 15% nitro? Fox does not recommend more than 5% nitro for that engine.

I was running 5% nitro in most engines at the time. The only engines that got more were my racing engines and my four strokes.

I purchased this gallon of Duke's in late 72 or early 73 ! ! ! !

David

Missle Mist K&B 100 K&B 1000 Frannys Fox Used them all, then started mixing our own and never used anything else. The high oil content for the fox stunt was needed to get a good 2-4 break,if enough oil was not used it would run erratic. High oil content is still used in modern stunt engines to get the correct run,these are low RPM motors and still use over 20% oil. DOUG