Very few projects start with a racing harness however that is exactly how Chuck Bridgman’s project began. He found an old RJS racing harness for eight dollars at a swap meet and decided to build a sports car around it. After searching for a while he purchased a 1979 MG Midget on Craigslist with a damaged engine but otherwise in great shape.
Once back in Chuck’s garage, his first choice for engine replacement was a 1182 cc flat-four from a Honda Gold Wing 1200 but it was too wide for the engine bay. His next choice was a more compact V4 from a mid-80’s Honda V65 Magna.
After some careful measuring, he found the V4 would fit nicely. So Chuck purchased a 1984 Honda V65 Magna motorcycle and pulled the 1098 cc V4 from the frame. The engine comes with four carburetors and makes 116 horsepower (87 kW) and 70 lb-ft (95 Nm) of torque. Chuck secured the engine in the bay using a custom mounts in the front, rear, and top. The front mount connects to the factory mount points on the car frame. The rear mount runs across the transmission tunnel. The top mount connects to the heater and battery shelf.
The engine runs the stock motorcycle wiring harness minus lights/accessories and custom length spark plug wires. It’s fed by the stock motorcycle fuel pump installed in the engine bay. Chuck connected the car’s accelerator and choke cables to the engine’s carburetors.
Chuck compensated for the powertrain’s clockwise rotation output by flipping the rear end. He accomplished this by pulling the axles, cutting the ends off the rear end housing, drilling new oil filler and breather holes, weld old filler hole closed, flip middle housing, weld housing ends back on, and install axles. He also used Lucas gear oil to help the pinion gear stay lubricated since it would now be at the top of the rear end.
He connected the motorcycle’s driveshaft to the car’s driveshaft by welding the Honda universal front joint and shaft into one end of a steel tube and the other to the MG’s output flange. The custom driveshaft routes through Isuzu Trooper carrier bearings positioned on the old transmission mount and transmission tunnel. The car made a terrible vibration on the first test drive. After researching the issue, he discovered the driveshaft needed the motorcycle’s cush drive. He welded the cush drive on the driveshaft along with another carrier bearing.
Chuck estimates the project took 100 hours to build and has been a blast to drive. How could it not be. The engine change and bumper removal resulted in the car’s dropping 300 lbs diet and doubling the horsepower.
As all projects go, there is always more work to do. Chuck wants to install a proper exhaust system and paint the car. He’s also looking into installing a Laycock overdrive system to help with bring engine rpm down during highway driving. You can read more about the project in Chuck’s build journal.