Need help with 383 setup

I can't help you with the Isky cam but I like the 509" lift MP I'm using in my 383, 71 Demon. The use of 906, or equivalent heads is a rule and I went one step further and pocket ported mine. I'm also using a 750 full mechanical Speed Demon on top of a single plane Weiand manifold. One bit of advise though, if you're going to use a high volume oil pump, MP or equivalent, do not use the MP windage tray. There are not enough louvers in the MP tray and under hard acceleration the oil doesn't get back to the oil pickup quick enough even with a baffled 5 quart oil pan. The simple fix is use a Milodon windage tray which has twice the amount of louvers.