I don't consider the "improvement" in burn rate or apparent octane rating worthy of tinkering with timing or mixture- - - -it's just a little fudge factor that might prevent detonation on a hard uphill pull, and keep the valve guides a bit slippery from the oily consistency of the Diesel. Back during the Korean war, most of the good-quality gasoline got shipped across the pond, and civilian supplies of gas were notorious for causing carbon buildup in engines. Aftermarket "top engine oilers" got pretty popular that dribbled a tiny bit of "tune-up oil" into the intake manifold through a TINY piece of copper tubing, about 1/8" OD. The oil supposedly lubricated valve guides and minimized carbon buildup on valve stems. Most of those systems used a 1/2 gallon glass jar under the hood with a needle valve adjustment that needed to be refilled every couple of months. That's where Marvel Mystery Oil got its start, I believe.
Jerry
