BBC 454 question????

[kiles_2001]

so I have a low mileage 454 that came with my truck... the guy told me it was rebuilt but after taking the heads off you can tell it had some miles on it but still very good, the cylinders have no ridge/lip cut out on them yet, the engine has been rebuilt at least once since the pistons are .030 over, they are flat tops with two small valve relief cutouts, the cylinder heads are 049's and that is where my question comes in... I have read in a few places tat flat tops with 049 heads will give me a low compression, will that equal low power? and also what camshaft would be good for it running a TH400 and 373 gears in the rear? any help would be highly appreciated...