Comp Cams Engine Camshaft 11-302-4 Fits Chevrolet GEN IV 396-454 Big Block Engin. Engine > Valve Train Components > Engine Camshaft. Computer Controlled 212/218 Hydraulic Flat Cam for Chevrolet Big Block 396-454. Fits Chevrolet GEN IV 396-454 Big Block Engines Originally Equipped with Flat Tappet Camshafts.Not Legal For Sale Or Use On Pollution-Controlled Motor Vehicle. For more than 35 years, the COMP Cams® mission has never changed: to produce the highest-performing products possible, provide customers with superior service, and to lead the industry in technological development. While the COMP Performance GroupT has grown to multiple companies and hundreds of employees, we still retain the competitive spirit and desire to be the very best that has positioned COMP Cams® as the absolute leader in valve train components.