Hi,
I'm trying to find out what's the difference between IO-540-C4B5 and -D4A5, the one Van's sells. According to specs the -C4B5 develops 250 hp at 2575 rpm (max) and the -D4A5 develops 260 hp at 2700 rpm. I read somewhere here that it has to do with the crank's dynamic counterweights are different but according to Lycomings parts catalog, those two engines have identical counterweights. Actually, those two engines seems almost identical, comparing parts.
Could it be that the rpm restriction is because of the engine/propeller/aircraft combo designation? I know that the -C4B5 is used on the Piper aztec.
Thanks for any enlightening input.
Fredrik
I'm trying to find out what's the difference between IO-540-C4B5 and -D4A5, the one Van's sells. According to specs the -C4B5 develops 250 hp at 2575 rpm (max) and the -D4A5 develops 260 hp at 2700 rpm. I read somewhere here that it has to do with the crank's dynamic counterweights are different but according to Lycomings parts catalog, those two engines have identical counterweights. Actually, those two engines seems almost identical, comparing parts.
Could it be that the rpm restriction is because of the engine/propeller/aircraft combo designation? I know that the -C4B5 is used on the Piper aztec.
Thanks for any enlightening input.
Fredrik