Dead stock bottom end quickness

This combo was run in the late 80's, so is a dinosaur set up. 69 440 short block with cast pistons, MP .509 lift cam. 906 heads with big valves, homeported with MP templates, shims cut out of pop cans and put under rocker shafts for more rpm. Motor rolled around on old tires to assemble because I didn't have an engine stand. 3.91 gear,29x10 slicks. Hooker fenderwells. 69 Barracuda. 11.66, was a real grin till a piston broke.