I don't know how old you are or what your time frame reference is,but I recall the old Pro-parts combo from the 80's. It was a 440 with 2.14/1.81 valves, pocket ported 906 heads,street dominator intake,10ish:1 compression 509 purple cam, 850 D.P. It made 511 H.P. and 522 TQ. I think with the .557 cam(or better/newer cam)and some refining it would surely be posible to surpass the results of 25 years ago.