FAST? Single Plane Intake Manifolds are designed to produce tremendous horsepower and high RPM torque from 3500-7500 RPM (Big Block Chevy), 4500-8500 RPM (Small Block Chevy, 351W Ford) and 4500-9000 RPM (289/302 Ford). All manifolds accept square bore, four-barrel 4150-style throttle bodies, such as the FAST? part #307603, and feature a fuel injector boss in each runner that will accept FAST? high performance injectors.