Completed the fuselage extension for my project. A fuselage extension has been required to balance heavier engines including the Mazda Rotary I plan on using. Although the engine will weigh only a few pounds more than a comparable Lycoming, I plan on adding turbo normalizing, intercoolers, and oil coolers in the engine compartment and a P-51 style radiator at or near the CG under the plane as well as an effective muffler system to keep it all quiet.

The fuselage extension was 18 inches and made of 1 1/2 inch angles as the primary load structure, 1 inch cross bracing angles and gussets made out of .063 2024 T3 aluminum plate. I used the general plans from Ray Ward's drawings that he used to counterbalance his Chevy 454 installation, but had to custom make each piece to ensure the angles and the gussets were strong enough for the job. I also dropped 2 plumb bobs, and ran a center string to keep it all straight. I feel confident that I'm straight and strong.