1st, welcome to the site! 2nd, I'm just going to throw this out there.......
"All the carb/intake/and cam that can be thrown at an engine can be thrown out the window if you have a bunch of leaky valves". Before doing ANYTHING, I'd give it a compression test, verify the valves are sealing and compression is pretty even across all 8. Then, and ONLY then, yes, a nice 4bbl/mild cam with a good dual exhaust will help it perform!