OK you have 416 cubic inches. I tell people this, how much HP can you build? 1 HP per cubic inches is easy, a few bolt on parts gets you there. I can do 1.5HP per cubic inch with some flow bench work and some computer modeling most of the time, so that is 624 HP So you want to be in the middle of that so very doable goal. Next is what kind of fuel do you want to run, what kind of engine vacuum and drivability do you need, and how much money do you want to spend? You burn air and fuel to make power fuel is easy to add, the air is the problem, so spend your money on decent heads, how much they flow will be the biggest piece of the puzzle.
I cannot tell you how much money and time you will save by using a good engine program to design your builds. I use two, performance trends is the main one, and one called pipemax. I sometimes build my own headers and pipemax calculates best runner size and length of tubes, it also has a good engine program built into it as well. If you get performance trends the manual that comes with it is worth more than the program, it will explain how an engine really works. Performance trends will calculate things like isle vacuum, cranking compression, spark knock and plot advance curves.
Plus it is just fun to plug in combinations and see how they would work.
https://www.performancetrends.com/Engine-Analyzer.htmI used to teach engines at a technical college and used the program in class explaining how engines operate. Next thing is how accurate is it? I just finished a 440 with a 1963 cross ram, program said it would make 605 torque and 615 HP it made on my dyno 605 torque and 600 HP pretty close, cranking compression and idle vacuum was exactly on the number. So put good numbers in and good numbers come out.
