I got a GMPP Fastburn 385 in my 66 impala.It is rated at 385 hp and I believe it.I weighed my car personally and it wieghs 4200 lbs without me in it.My car is originally a powerglide car and therefore has a 2.73 rear gear.The motor has plenty of power to move such a heavy car with airplane gears.They call for a 750 cfm vac sec carb,but I think my 650 mech sec does much better.I run on 89 octane fuel,can burn my 255/60r15s in second gear EASY at a 20 mph rolling start AND I get 20,YES 21 mpg on the highway with the a/c off.16 mpg in town with a/c on.I have put over 45,000 miles on it in the last 3 years with no problems whatsoever.It will run a high 8 (8.6-8.80s) second pass in the 1/8 mile,leaving like a sissy to protect my original(read:worn out)rear gears with 275,000 miles in them.Has a nice idle that sound kinda lumpy without be too much to ignore.Sounds good but not enough to irritate you if you drive it in town everyday.Bought mine straight from the dealer,but I think Pace Performance has the best deal on these particular motors.I would LOVE to see what it would feel like in a setup like yours
HIGHLY RECOMMENDED .Especially for an everyday rider like mine.Good luck and let us know what you get!!