Hi Harry, I'm Duane from Gilman Springs. I always fly with Terry at the Cub flyins at your field. My Cub is the 1/4 scale blue clipped wing model. We got Rained/blown out this year, but Mel and I were there early AM, paid our $6, and were rairin to go! Your motor sure sounds like a Quadra, but as w8eye says, 4 bolts for the muffler....Pics would be good.... Space worm, weight of quadra in my pic, with spring starter, flywheel, mounting cone and muffler is right at 4lbs. Very compact motor, rear muffler and carb is tucked in close to the side. I buy them whenever I see them for sale at swap meets! :^) Duane