Brodix 1001001 Track 1 cylinder heads for Small Block Chevy engines. Assembled with 2.080in intake and 1.600in exhaust valves, 221cc intake runner, and 67cc chamber. Features 1.550in springs (240 lbs closed, 550 lbs open, .700in max lift), angle plugs, and A-356 aluminum construction. Designed for drag or oval track racing, offering significant horsepower gains. Sold as a pair.