ORIGINAL: captinjohn
I stated my qustion wrong in a way. The amout & $$ of fuel each product would treat one gallon of fuel is the question. I read you need a lot more castor per gal (20%) but synthetic you would use far less per gallon of fuel because of the much higer ratio you use(40-1 50-1 100-1) depending on brand of synthtic used. Gets kinda hard to figure this all out??? So there then is another question...what synthetic oils mix with alcohol and can you use a 80% alky/10%castor/2% synthetic mix??? Thanks capt,n
Nope. As stated before, that 80:20 mix is a standard adopted for universal competition use, and that is all you should read into it. If you are thinking of the ratios you see printed on 2-stroke oil bottles, like 50:1 or 100:1 - those are NOT recommended ratios for the oil to be used at. These are the maximum level to which the oil can be diluted and still retain film strength. Those super thin ratios are for gasoline burning two strokes with needle bearing con rods and whatever else that allows it.
The only ratio to mix fuel for your glow engine at is that recommended by the engine maker or another sensible authority on the engine itself. So no, you can't replace 10% of castor with 2% of synthetic is the short answer. But you could very successfully use a 80-82% alky, 18-20% oil fuel, of which the oil package itself is a blend of castor and synthetic to the liking of the engine. An 80% synthetic/20% castor oil package at 18-20% of total is commonly used with aero engines of contemporary manufacture.
MJD