I have run a two different K&B 4011's on Davis 1/2A fuel. On one, after the glowplug was left on for maybe 20 sec, it would run fine. The other would undercompress (thicker head gasket maybe, never checked) without the glowplug connected. The engines ran with the Super Tigre NVA screwed in 1 1/2 turns compared to glow. Both turned a 11 x 5 APC at 9,700 both glow and diesel. These were engines set up for CL stunt. I think you could run diesel fuel in most glowplug engines with maybe a little fiddling with head gaskets.

Jim