QUOTE(Dman @ Jun 2 2003, 02:51 PM)
Favorite old motor?
If anyone knows much about these speakup!
Type 547, AKA "Carrera four-cam" or "Fuhrmann four-cam". Hellishly complex DOHC Bug motor (sorta-kinda-maybe-but-not-really) putting out an improbable amount of power for the day from a little displacement. They ranged from 1500cc up to 2000cc, and put out anything from 100 HP to 200+ HP. The lesser-powered ones were motors for street cars, the big numbers were for motors built for the factory racers.
The Abarth Carreras all had them. The 356 Carreras did as well. Most of the Spyders did (the first couple got pushrod motors as the four-cammers weren't done yet; a later experimental Spyder got one of the 8-cylinder Formula 1 motors and possibly there was a Six put in one). The 904 was designed to take the 547 or the new 911 six-cylinder. Pretty much all of the zoom-zoom cars that Porsche built up through about 1964 or so had these engines.
The dual overhead cams were driven by layshafts with beveled gears. Two distributors because the engine was twin-plugged to run higher compression. Usually the powerband was waaaaay up high. Shim-and-bucket valve adjustment, which took even a factory-trained mechanic roughly forever. I recall hearing that it took a factory-trained mechanic 80 hours of work to assemble the motor. IF nothing went wrong...
Good example of the German trait of, "Ve vill make zis as complex as possible--und ve vill make it verk very,
very gut indeed!!"
--DD