AC-4 4 CYLINDER OHC ENGINE

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This is a custom OHC 4-cylinder engine I've designed in Fusion 360 from scratch, drawing on decades of experience in the automotive industry. The AC-4 combines elements of various engines I've worked with over the years to create something unique. I'll be machining this entire engine on a 4-axis CNC mill to have it running as a 4-stroke glow engine soon. All parts are 3D printable, although I still need to complete the files - I'll add them as I make progress. The only components missing at this point are the timing system, crank seal back plate, crank pulley, lash cups, and tensioner assemblies. Coolant and oil passages were the most difficult aspects of this project so far. The cam LSA is set at 112 degrees, based on SBC cam profiles, to achieve good idle quality due to reduced overlap. Everything else in the design was created from scratch. If you're wondering about the carb shown in the pictures, it's an O.S. 20J - I designed the intake specifically for this carburetor. For the pumps, one is an oil pump and the other a water pump, both of which I also designed. To assemble the engine, you'll need to print: 2 housings 2 backplates 2 shaft bushings 2 keyed rotors 2 free rotors You'll require M3, M2, and M2.5 cap button head Allen screws for assembly, as well as 2mm rods for pump shafts. I haven't yet addressed valve springs and lash cups, so more information will follow on those components. I hope you enjoy this project!