[jonnyk]

For a 393 I'd be tempted to put a TFS-R on it, or some form of box intake. You don't want to choke off those cubes with a tiny short runner intake.

And a 393 will cost you a fair bit more to make work than a 302-based engine, due to the size differences in lots of areas, and the difference in lifter setups you'd have to use to go hydraulic roller.