The professionals at Indy Cylinder Head are determined to raise horsepower to the next level, without sacrificing reliability. The 600-13X is a true wedge, 13 degree valve angle head, with the potential of 500CFM of air flow. The 4.840 bore center line is a necessity to increase valve diameter to 2.400″ on the intake and 1.900″ on the exhaust without shrouding the valves. Lightweight, reliable 1100 + HP engines are finally available for the true wedge racer. Build a 655″ cid with these heads and you will have a mid seven second ride with any tube chassis car. A complete 655″ cid Big Wedge Engine weighs only 485lbs.