Mine is more complicated because it's a competition set-up. The buzz box is of my own design and I use a pre-mix fuel injected into the pipe just upstream of the plugs. You can let the engine trigger the extra coil, but it usually starts missing and fouls the plugs (at least mine did).

Flamethrower update...I used straight gasoline in my flame tank and had some rodder buddies cook weenies on my pipes, hot rod lunch food for sure. They had a funny after-taste, though....

You know, I thought of something sweet. What if I had the flamethrower connected to a remote, with a solenoid to pull the throttle. I could flame' from 30 feet away!!!