Big horsepower 318 builds

You wouldn’t need that much.
Wouldn't be that hard, trick flows with 10.5:1 285-295 ish cam with the right intake/carb and exhaust but for most having to spin to about a 7500 rpm for peak power is on the high side and needing 4.88-5.13 + gears and 5000-6000 + rpm stall is a little much. A 408 would do it around 6000 rpm a 440 @ 5500 rpm, 500+ @ 5000 rpm.