The largest and most successful cam that I used for both SB/BB was the MP 590. I made good power and it had longevity. These were back in the 80's when iron heads were all we had. With better flowing heads, intakes, carbs ignition system, etc as per present day, I thought that a cam in the 550-580 range could get the job done and be reliable(500-700 passes per refresh). I did my fair amount of power and breakage issues with my hemi MP car and my VW powered Gasser. Been there, done that, and that's how I race anymore.