Now each piston is brought up to TDC and the distance from deck to the piston is measured with a dial indicator. We found our pistons were 0.0010 down in the hole, which some builders would run. Speed-O-Motive likes to put the race engines at a zero deck. We asked Jeffrey Strech shop foreman/lead cylinder head/engine designer to explain the benefits of the zero deck and here is what he said. "We set this motor to a zero deck height because it will provide us with the optimum quench distance of 0.040. So when the piston comes up to TDC the quench area, or flat area of the piston and head, compresses the air fuel mixture and sends it at high velocity throughout the combustion chamber. This movement tends to cool hot spots, suppress detonation and increase power."