The Magnum has plenty of power with room for more with its"quench" style heads and roller cam its an excellent engine for a conversion.as good as a Shivvy or better.
PS my 93 Fullsize SWB pickup ran 14.94 in the quarter with headers, exhaust, mopar perfomance computer,,modified throttle body, on stock tires and 178k on the engine.and it still managed 18mpg on the highway.