Best 318?

[E Strong]

I want to build a street engine using a 318. It will be put in a Plymouth Sundance. I owned two 1970 Satelites at different times. The first one I bought in 74 with 44k on it. That car was amazing for a 318 with only a 4Bbl. and Headers. No internal work was done on the engine. Question, What are the best 318s, after 67? I know that the ratings were highest for 68-71.
Any assistance on this would be greatly appreciated.