I recently rebuilt a 350 bored 0.030 over, with new pistons, xe comp cams 262 cam, double hump heads with 1.94/1.60 valves. on the top it has a holley double pumper 650 4150 flange and an rpm air gap intake. malory distributor ...with a freshly rebuilt th-350 non lockup tranny with 2200stall converter. The rear end I still have to install is a borg warner 3.42 or 3.45 gear ratio posi.

U have all crossed by my thread on the possibly engine damage that occured last week. As it may not really be the internals that are the source I was thinking that this would be the perfect time to step it up a little for horsepower.
Last year when I took it to the dyno , thats was with the 650 edelbrock thunder series that had an issue at initial pump shot ....well with this carb, a REEAAAALLY bad cranckcase lacking ventilation(leaking quart of oil on the spot)...87 octane,,8* timing...10.2;1 around...cr .a flex fan directly connected to the water pump, small 10x2 air filter.....I made 280 something at the wheels...judging by the crappy 2.93 rear end and everything we used the 21% drive loss to get close to 340 or so horsepower.

Well becayse i already have everything like the intake carb block and other parts in the 350....I was thinking of building it up to a 383. the bottom line is that i am looking to get about 430 - 450 crank horsepower. I know that the heads are the biggest factor hands down in this however I dont know if I should go with the 350 vortec heads and work those or just try to find some used aluminum heads. I dont want to spend too much on this but i know when its all said and done i will probably have to get new heads, maybe 0.30'' higher lift cam

can anyone just run by a few quick routes I can take..thanks in advance