These days it is pretty easy to build in excess of 400 hp and that under 6000 RPM with modern intake and head designs, you almost have to work harder to avoid that end. That is of course engine dyno power with free flowing long tube headers, actual installation with intake and exhaust system space related compromises certainly eat into those numbers. By that the intake starts at the air cleaner which is dictated by available hood height and intake height. Just getting the air into the carbs air horn can be a big power robber. Then the exhaust headers in a tight engine compartment is another. So installation compromises will easily lower these 400 hp numbers down to 350.
Physics being what physics is you will find that similar cam timing, valve sizes, combustion chamber configurations, and compression ratios between a wedge Ford 351, Chevy 350, or Chrysler 360 delivers very similar power numbers. There is plenty of info out there that shows that these engines with a cam that times and lifts in the neighborhood of the Comp XE268H, with GTP, Vortec, or Magnum heads at about 9.5 to 1 will on an engine dyno deliver right in the neighborhood of 400 hp. The details of porting, rocker ratios, valve sizes, intake, carb choices, etc. push the numbers around from about 380 to 410. After market heads will push the numbers toward the upper end or a bit higher with less effort to porting and rocker ratios for example.
This power level with these modern components is far from a high strung engine. This is very streetable without needing stiff gears and with a manual shifting you arm to exhaustion, if an automatic cam's in this timing range are at the upper end of factory stall and are probably easier to live with on the street with a 2500 RPM converter, but don't require anything amazing.