You are right, we did use nitrobenzene. It is also called Oil of Mirbane, and is the great smell when you open a fresh can of Kiwi shoe polish. We also used propylene oxide, tried ethanol (did not work well), very high nitromethane for speed events and rat racing, when we could mix up our own fuels. Down Under, they use about 3% acetone to aid in ignition of their model engines. I also made fuels earlier with Mobil Jet oil. Does not take a high percentage, but did not work all that well. Most countries use much less nitromethane than we do here in the States. I remember using Klotz Techniplate oil in the King Orange Internationals in Miami, FL when it was first introduced. It is a very good lubricant for model engines and I personally buy 30-gallon barrels of Klotz Techniplate, gallons of Benol racing castor and 5 gallon pails of nitromethane, and 55-gallon drums of M-1 racing methanol (VP Racing). Getting the nitro is a bit easier for me, I have a chemistry degree in my bag of degrees and have been mixing my own model fuels since I was 12 years old. Back then, I flew contest rat racing and combat, both control line. Could not afford radio control, had to get a real job to be able to do that. :-) In the earlier days, i raced with K&B .29 and .35 engines, before the more powerful .40s were introduced. Had Cox .010, 0.020, .049, OK Cub .049, old Forester? .99, Cyclone Super .60, you name it, I had it. Also had the gray metal case ball bearing racing McCoy .29 engine. redhead, NOT the $8 one in the plastic box, but the $15.99 racing .29. Had to cut down 8 x 9 props for that on my rat racer. Also had to bore out the diameter and re-balance the props. Could beat a lot of .35s with that engine. Last remembrance, at the King Orange Internationals, we used to go and get a conical plastic coated cardboard bottle of A & W root beer nearby on 27th Avenue in Miami, about where the Junior College is located now. The root beer was 25 cents for the quart!