I just tried my first gas glow mix conversion, using an old Ryobi engine. I used 2 parts regular gas and 1 part Mach 1 fuel 15% nitro as this is what I have on hand. I took an old Ryobi spark plug, knocked the guts out of it, turned a small brass plug to fit the hole, silver soldered it in place from the top side, used an end mill to clean it up, then drilled and tapped it to fit the glowplug. I tried a new OS # 8 plug and ran the engine, but it ran very poorly. Needle valve adjustments would not help. I then remembered having read in these postings about using an F plug, so I tried one and it made all the difference in the world. The engine will now go from idle to wide open without hesitation and will run as long as you supply it with fuel. I plan to try the mix on one of my flying converted ignition gassers perhaps tomorrow.
A question: I read where it is recomended to use premium gas and 10% nitro glow fuel for the mix. Will the higher octane gas make a difference over the regular? Either will run my converted ign. gassers and I can't see a difference.
W5RA