HO on a SO motor

[jlwelding 24]

I have heard a ho will not work on a so is this true? At the sametime a so will work on a ho right?

[Mopar1973Man 6,490 5 Vehicles]

VP44 pumps... Yes this is true... a SO VP44 pump on HO engine is fine. But you CANNOT put a HO VP44 pump on a SO engine.

[cummins2k 1]

I wonder why this is that the SO pump is compatible with the HO stuff, but the HO isn't compatible with the SO?

[Mopar1973Man 6,490 5 Vehicles]

Best I can say is the timing and fueling software... Something about that... :confused: I don't think there is any phyiscal differences...