Stock Magnum 5.2/5.9 camshaft w/carb?

cudak888 said

My fear (and assumption) was that the factory Magnum camshafts may be ground with a short duration and wide lobe spacing, thus timed to capture a more accurate air/fuel mixture from the multi-port injectors vs. a longer duration to ingest the less-accurate atomization of fuel traveling through the runners from a carburetor. -Kurt

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Perhaps think of it this way... with the MPFI, the fuel is just being added into the air at a different point and in a different way and with more accuracy with the O2 sensor enabling the computer to manage the A/F more accurately. But the engine as a self powered air pump works the same, with an intake throttle plate used for power control; the carb interacts with this in the same basic way as the MPFI.

There MAY be considerations to optimize the cam a bit for taking advantage of the MPFI for economy or emissions, or to compensate for the carb operation, but you are still using the cam to manage cylinder filling, and balancing that against operating CR (DCR) over RPM.

BTW, your questions are good; I am following them as I help my son into his 1st V8 build experience. After us working on his 4.7L Dakota engine and us racing TBI turbo'd engines, he wants the relative simplicity of a carbed engine.