The camshaft isn't the problem. There isn't a non-offset rocker head that will support a 4" stroker to spin much higher than 5500-5800. You can cam it, header it, single plane it, carb it, till the cows come home, won't help. Part of my mild disdain for strokers is exactly this. J.Rob
I’m not sure what the definition of “much higher than” but mine runs best and pulls hard to 6300-6400 rpm. With nowhere near the intake or exhaust flow that is very easily accomplished. Stock casting intake and exhaust manifolds.
