What cam do you have in your magnum?

A 570 is too small for that combo. I ran a 670 on the street on my Magnum.

Also, its probably best to get a custom cam. As magnums only came in trucks, all the shelf cams out there seem to be truck oriented.Your car can use more cam that that in all probability.

You can check out the way I did my car at www.magnumswap.com

Steve