Skunk2s engineers looked to the popular 06-10 Civic Si*s RBC intake manifold for inspiration when developing our Pro Series Intake Manifold for K-series engines (excluding 06-10 Civic Si) and went back to the drawing board. Each of Skunk2*s Pro Series Intake Manifolds for Honda*s K-series engines feature larger plenums and shorter, oversized runners when compared to the RBC, and are cast with thicker wall material, leaving room for further porting for high-horsepower applications. Instead of producing a manifold with a significantly oversized plenum and excessively short runners that would sacrifice mid-range power, Pro Series manifolds were designed for the *street enthusiast* who wants more power but doesn*t want to sacrifice mid-range performance to get it. The results are improved airflow, an enhanced venturi effect, and both mid-range and top-end power gains. Skunk2*s all-new, cast-aluminum Pro Series Intake Manifolds for Honda*s K-series engines are a direct-fit replacement for all K-series engines (excluding 06-10 Civic Si) thanks to their unique, patent-pending throttle body flanges, which are compatible with OEM throttle bodies as well as those as large as 76mm. Pro Series manifolds also incorporate an angled-runner design, which allows for ample hood clearance on *88-*00 Civics and *90-*01 Integras with K-series engine swaps, as well as additional core support clearance on *02-*05 Civic Sis. Pro Series Intake Manifolds offer horsepower and torque gains greater than the popular RBC manifold but without compromising mid-range power output. The design incorporates runners that are similar in length to the RBC*s but with larger bores, a special tapered design, as well as a larger, tapered plenum that together preserve mid-range power but increase and accelerate airflow to allow for significant top-end power gains. Pro Series Intake Manifold runner exits are also machined and hand-finished to best match the cylinder head*s ports. Pro Series Intake Manifold; 70mm TB Opening; Can Be Inlet Matched To 76mm; Uses Factory Water Neck; Black; Ideal for turbocharged and naturally aspirated applications.; 70mm throttle body opening can be port-matched up to 76mm.; Not compatible with 06-10 Civic Si K-series engine.; Re-uses OEM Coolant Neck