RHS™ Pro Action™ 180cc cylinder heads are the perfect bolt on head for smaller-displacement Small Block Chevrolet engines. Ideal for 262 to 350 CID street engines, Pro Action™ 180cc cylinder heads are the hot ticket to making up to 325+ flywheel horsepower. With superb finished quality and a long list of desirable standard features -including top-quality COMP Cams® components in fully assembled models, Pro Action™ 180cc cylinder heads deliver maximum value for your performance dollar.