Subaru EJ20 Boxer Engine - Moving Model

Designed by: ericthepoolboy
Hardware Kit and Build Support by Maker Rx

Experience the unique engineering of the Subaru EJ20 with this fully functional, 3D printable scale model. With moving pistons, belt-driven camshafts, and a motorized crankshaft, this build captures the spirit of the original boxer engine in stunning detail.

Originally designed by ericthepoolboy using CAD references and technical documentation, this model captures the unique flat-four engine layout with impressive detail. Maker Rx teamed up with Eric to offer an official hardware kit that includes all the non-printed parts required to complete the build, making it easier than ever to bring this project to life.

📦 What's Included in the Files:

• Complete STL file set for the full EJ20 assembly
• Functional pistons, crankshaft, camshafts, and belt drive system
• Cut away for viewing internal motion

🔧 What You’ll Need:

• FDM 3D printer
• Basic hand tools
• Super glue and soldering tools
• Optional but recommended Maker Rx hardware kit

⚙ Key Features:

• Accurate horizontally opposed piston motion
• Motor-driven crankshaft and belt-powered cams
• Realistic scale design with dynamic moving parts
• Great for display, education, or just fun for gearheads

🛠 Official Hardware Kit:

To simplify the build process, Maker Rx collaborated with Eric to create an official hardware kit. It includes bearings, belts, fasteners, rods, magnets, a DC motor, and more. Everything you need besides the printed parts.

Order the kit here: https://www.makerrx.com/products/mrx2

📚 Build Help and Resources:

• Video walkthrough on our YouTube channel

🧪 More Engine Projects:

The EJ20 is one of several engine designs supported by MakerRx. Check out our kits for the LS3 V8, Flathead V8, Rotary, and More.

🤝 Attribution:

Original design by ericthepoolboy. MakerRx supports this design through a direct collaboration with Eric to offer a complete, high-quality hardware kit and supplemental build resources.