Shoot for 9.0 to 1 to 9.75 to 1 compression ratio with good quench, I'd look for a good Holley 850 D.P. or if you can find a good used Holley 950 HP buy it The 950 HP are smaller in CFM than the 850 D.P. are but they work real well As far as the cam I would(and do ) use the Comp Cams XE285HL grind installed between 108 to 105 intake lobe center. Make sure and get the compression ratio correct the first time, don't guess at it Better yet hold off on the pistons and buy the Eddy RPM heads first and then buy pistons to make between 10.0 to 1 and 10.75 to 1 comp. ratio I've built a bunch of 440 motors like yours with 906 open chamber heads and never had a problem making 500+ HP between 5000 RPM and 5900 RPM depending on which cam was used and 550 Ft lbs on CA pump gas another really good choice is used the 400 block and have the 440 crankshaft rod journals offset ground to 3.90 stroke, have the mains and counterweights cut down for the 400 block and make a storming 464+ C.I. motor, tell all your freinds and enemy that it is a 383 bored out As far as the converter make the motor first and then buy a really good converter, not a cheap rebuilt standard autmotive trans shop one , to match the motor I like and use Continental Converters in Los Angles, CA