1972 dart 318 want to make the tires spin

something doesn't sound right. 325hp should be able to break the tire loose. I'm assuming your 7 1/4 is not a suregrip.
I agree . I have a bone stock 318/727 (headers/1406/performer 2176) and a 291 geared 7 1/4 and I can roast the tires at will