BMP 061040 - Intake Manifold Chevy Small Block 4150 Carb FlangeBill Mitchell Products Intake Manifold Chevy Small Block 061040 4150 Carb Flange Developed on the dyno and proven on the track. BMP intake manifolds on average show gains of 10+ HP over the competition . Street, Drag or Circle track racing, drivers love the low rpm throttle response and the top end power. No extra clean up required, just bolt on and go. TECHNICAL INFORMATION: Port Size: 2. 000" x 1. 180" Rectangle Port RPM Range: 2500 7500 Overall