A couple of remarks. First, keeping up on the
Autobahn may be more of an issue with the rear end gears rather than the engine. See this thread :
https://www.fordbarn.com/forum/showthread.php?t=288337. Second, the cheapest and easiest way to get more performance out of a flathead Ford is to rework the heads for increased compression and optimum quench. It has been covered here and on the H.A.M.B. many times.