JimD
50cc
We have built two of these models and have made this modification on both. On the first, the rear part of the canisters were open to the interior of the plane. This didn't seem to cause any trouble (even on some very warm days), but we decided to make an enclosed tunnel on the second model. Here is a picture essay of the modifications we made. The engine used is a Desert Aircraft DA-120. Canisters are MTW-75k front dump. Headers are KS 90mm drop with flex section.
This model is being used as an aero towing tug for giant scale sailplanes. We put about 50 hours of flight time on the first model and sold it. This model now has about 10 hours of flight time with zero problems. For our purpose, adding a little extra weight to the model is not a problem. The fuel tank is a 100cc DuBro and gives us about one hour of flight time doing towing duty.
This model is being used as an aero towing tug for giant scale sailplanes. We put about 50 hours of flight time on the first model and sold it. This model now has about 10 hours of flight time with zero problems. For our purpose, adding a little extra weight to the model is not a problem. The fuel tank is a 100cc DuBro and gives us about one hour of flight time doing towing duty.