I had a similar problem with my Cobra, sounds silly, but it was actually too much initial timing, 21 degrees. It smelled flooded. When it didn't start I tried flooring it because supposedly it is supposed to stop delivering fuel with full throttle when cranking, but that didn't work, so I tripped the inertia switch and then it could clean out and start. I guess try that. It did this consistently on warmer days until I figured it out, don't know why anyone would put that much timing in, but I put it to 14 initial, and no problems since. Also could maybe be weak fuel pump. Good luck.
