In going to the hot rod shows, I noticed that the flames could not be sustained. They would have to let off the gas and let it build up and then kick the throttle wide open to see the fantastic flames come out. Some of the good ones could modulate the throttle somewhat and almost maintain a constant flame.

These guys seemed to using some kind of kerosene based secondary combustion aide.

WD40 itself is rather flammable. Try it again using real WD40. Some carb cleaners are not flammable.

Enjoy,

Jim