pitbike manifold. 28mm EFI capable. (casting patterns)

thingiverse

After several failed attempts with lost wax (PLA) castings, I decided to switch to a traditional split pattern set. The manifold features a 30-degree cant off the engine's centerline and a 26mm bore, making it compatible with 28mm EFI throttle bodies like the R15 or Ecotrons that fit Honda Cub-based engines from Lifan, Ducar, and more. Designed for turbocharging, this setup directs airflow perfectly into an intercooler. The manifold also includes bosses for machining MAP sensors and injectors. Specifically crafted to spray fuel directly onto intake valves, this manifold works with both carbs (like the PWK/OKO 26mm) and EFI systems, requiring only a blanked-off injector port or core breakage for carb setups. I changed the core boxes to prevent warping during printing and used greensand for cope and drag, along with sodium silicate for the core. After creating timber frames and ramming up the mixture, my first attempt was a success and is currently in operation – my very first proper casting experience. If you're not interested in melting metals, I'll produce these manifolds for $35 plus shipping; just let me know!