Getting the volume on domed pistons that have been radically altered, either by profiling or fly cutting, will require a direct measurement. To do that, place the piston down in the bore a precisely measured amount (usually .500 inch), and add grease to the ring land area to seal the piston to the bore. Now measure the total cc's it takes to fill the cylinder to the deck with a burette. Compare the measured volume (cc's) to the mathematical volume of the cylinder at .500-inch depth. The difference is the dome volume or clearance. In this case, a 4.350-inch bore at .500 inch down has a volume computed mathematically of 121.7 cc. With the piston deck set at .500 inch down, we measured 114 cc of fluid to fill it. The missing 7.7 cc is the net dome volume.