Pistons: Porting, Aftermarkets, 660's Piston Discussion

I wanna stress how much lower-end-displacement is gained, quickly, when porting pistons - aluminum is around 2.4g per cu mL (1CC) so the usual "cleanup of casting only" job that removes 5g is already a 2cc bump to lower end displacement (just like hogging out the lowers to 'properly' accommodate a wider throat to the uppers) so this may/may not be desirable, but - if using a big bore head - suddenly it becomes "normal" insofar as it 'balances' against the newfound, top-end displacement (so you're not shifting your peak-power very much in either direction, IE higher relative top-end favors middle range, higher lower end should push your peak power higher in your RPM-range)