Do some searches on this website. I'm sure you'll find adequate info. You might also talk to Tom Langdon at Langdon's Stovebolt or the folks at Patrick's in Arizona. They were very helpful when I built my truck, 261, stock 261 cam, bored 60, shaved 20, port & polished, 6=8 intake, 390 Holley 4 bbl, Fentons, 50-series Flowmasters.