Use the 509 so it runs like crap with that carb. Then you'll get sick of driving it and park in the shed where it will become a barn find in 30 years. I think the 509 cam created the barn find Mopars since the engines ran so poorly with them. The 509 + 850 DP combo turned lots of nice 440 engines into stinky, plug eating piles back in the 70's.