Honest Charley Popular Mechanics article... http://www.popularmechanics.com/automotive/motor_cycles/2003/7/honest_charley_flathead_V8/
Yup. Although that's the 136 ci "60 horsepower" flatty. The rest of those also went into sprint cars. I think that bike looks great. It would sound better (and be a lot more fun) if it had more than one gear.
I love those bikes. Unlike the bikes with the SBCs those actually look like the engine fits. I always thought the SBC bikes were rediculous, besides they looked like they'd be a ***** to ride anyway.