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I’m developing a high-rpm aluminum cylinder head and rocker system for an air-cooled engine and I’m looking for a CAD/CFD specialist to refine and optimize an existing cylinder head design—not start from scratch. You’ll receive a fully modeled cylinder head (see attached image) that already matches the engine’s interfaces (stud pattern, cylinder spigot, cam carrier interface, external envelope), plus an initial combustion chamber and port concept. The goal is to turn this into a castable, machinable, high-performance head that supports a 9,500 rpm, with 52 mm intake valves, 44 mm exhaust valves, twin plugs, and the ability to run both 6 mm and 8 mm valve stems via interchangeable guides and hardware. A major part of the project is serious CFD-based flow development, not just pretty surfacing. I want you to: Model and report intake and exhaust flow at 2 mm increments of valve lift (e.g., 2–14 mm) so we understand the whole curve, not just peak CFM. Optimize port and bowl shapes to hit targets like ~280–300+ cfm on the intake at 28" with strong mid-lift performance and good velocity. Spring geometry should be compatible with common performance parts: Honda K20/K24-style dual springs on the intake and 2JZ/BMW S54-style springs on the exhaust, with realistic installed heights and clearances for up to 15 mm valve lift. Rockers will use the existing cam carrier’s cam and rocker shaft locations, with a target ratio of ~1.5:1 and proper clearance to retainers and aggressive cam lobes suitable for 9–9.5k operation. Key deliverables include updated solid CAD models of the cylinder head, intake and exhaust rockers, valve seats, and valve guides (common outer geometry with 6 mm and 8 mm bore variants), plus CFD-backed port and chamber development with: (1) flow vs. lift plots at 2 mm increments, (2) velocity/streamline visualizations, and (3) clear before/after comparisons. I’ll also need a set of section views showing valvetrain clearances at full lift, ports and chambers, and cam/rocker regions. I’m especially interested in your recommendations on spring installed heights, seat/open loads, cam envelope, and any geometry tweaks that improve casting and machining robustness.