Flatheads? You mean those cast iron wonders from the 30s? Nahhhh, never heard of them.
My first car was a 34 2door. Put a 48 Merc in it then a 283 Chevy out of a dump truck
Welcome aboard, and I'd like to see a pic of your trike; I've got one too. http://motorbicycling.com/f44/2doors...ike-13591.html