Donald, The original Ercoupe design called for an engine which was designed and built by Erco. It was a four cylinder inline arrangement. The cylinders and plugs were at the bottom of the engine. The cowl for this configuration was actually very streamlined and actually came to a point behnd the propeller (you may know that Fred Weick's earlier work was on propellers and engine nacelle design... he was about efficiency). It was decided instead to use the production Continental engine available and forego manufacturing and supporting the inline themselves. This lead to the wider cowl we know, with its gills, air intake nosebowl, and the sparkplug humps. I believe any cowl you see today without the humps is a modification allowed because the sparkplug wiring was modified on those aircraft.
Others here can give you more details and perhaps a more accurate recounting of this, but in a nutshell that is why you see two or three (counting the prototype) cowl arrangements. I like the bumps myself... they add character. Best, John On Sun, Jan 31, 2010 at 9:54 AM, Donald <[email protected]> wrote: > > > What is the story with the bumps in the cowling? I had been led to believe > that the bumps had to be added because of different spark plugs/harness, I > know my Ercoupe just very recently had them added. I was surprised therefore > to notice that serial number one in 1939 had the identical bumps! What gives > with the bumps or lack of bumps? > > >
