There is a theoretical theory (see what I did there?) that you can predict (n/a) the
max power an engine can make, from cylinder head flow. There is lots more complexity to it, but bascally... 2hp per cfm.
So if your heads flow 300cfm, then the most to expect would be roughly 600hp.
From what I have read, stock magnums are good for around 220 cfm, so...400 on motor should be very doable.
Then add as much nitrous as you dare.
Engine masters got 600hp out of a 305 Chevy with a stock short block, before they blew it up. 250 shot. Nitrous guru Monte Smith said it shouldn't have blown up, even at that level. He said they didn't pull enough timing out of it.
