i use a 337 on my 580".it does very good,considering you can close a stock hood with it.on my motor i gave up about 70 horsepower to a 440-3 w/ dominator.
the ports are small for a max wedge.it took alot of work to open them up to the ports in my 572-13,s.i'm getting ready to try a 337 on my 500".i will try alot of manifold combos,and post the results.