[jhv48]

Just for comparison, my first 427 small block was a Roush and after putting on 3" sidepipes and a quickfuel 850 mechanical secondary carb, it put down 440 hp to the wheels with no other changes.

Yours should be similar. Start with your timing. A total of 34 degrees is a good place to start. New plugs would be a good idea too. No telling how long they've been in there. That's all there is! Air in, air out! As long as you have fuel and properly timed spark, you should be good to go. Hold a mirror into your sidepipe and see how large or small the interior baffle is. Mine was 1 3/4" inside diameter (really choked the crap out of my motor) before I changed it out to 3". That was the biggest part of my horsepower gain besides the carb.

Good luck. The horsepuppies are there, you just have to figure out how to let them out of the barn.