505 vs 440 is mostly gonna be a big increase in TQ with just a little HP increase, TQ breaks parts, you get to a point where you can easily make the power with good modern top end stuff to run what you want and any more TQ means upgrading from 8 3/4 to dana bigger tires higher gears (put more stress on trans and driveshaft u joints...) bottom line is it is just so easy now days to run low 11s with even a stock 440 short block and carefully selected modern heads and cam that it is almost not worth bothering with the extra cubes. Don't get me wrong, I love big TQ but there is a point where it is just not much point, on the street a 440 can easily make 500lbs tq and make hooking up nearly impossible already and at the track when it does hook you got to upgrade lots of stuff to keep it from breaking stuff, are you u-joints gonna handle 1300LBS plus TQ? Driveshaft? Trans output shaft? Can your input shaft handle 600lbs?