Define 'by design'.
The stock steel heads were milled to increase compression, the aluminum heads already had the smaller pocket over the valves. 14 to 1 sounds about right for alcohol. Look up "Hadacol Boogie".
The design limitation of the flathead is constricted breathing and the solution is a GMC 6-71 supercharger. With that it will match an OHV V-8. A blower and Ar-Dun heads was the best of both worlds.
Or maybe a turbo, MSD ignition and a 4-speed box? One of the nice things about a flathead, beyond the narrow overall width, is the exhaust is routed through the block and so they run really quietly.