Cam,
I don't think it would fit in the cowl. It flies on a 100 and on a 120 it lacks nothing. A 150 will fly the 3.1 just fine. We did all the original testing with a 150 and Jerry Hailey flew a full season in IMAC on the 150 in the 3.1
Al
I am demonstrating this, for those who wanted to know. I will not be doing this. But, since I had a DA 150L laying around! I tested it to see if it would fit in the cowl.
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This is a DA 150L and behind it is the cowl for the 2.8 MX2
next picture, is a cowl for a Carden 40% Extra 300 (on the right side of the photograph), and to the left side of the photograph is the cowl to the 35% MX2.
Here is me putting the DA 150L inside the cowl of the MX2:
I would not recommend this. The spark plug tops are touching the sides of the cowl, and also "stretching" them out. No way it would fit inside the cowl, with the spark plug boots on. Plus, not needed! It will make balancing the airplane more difficult since a 150 motor weighs more than a 120 cc motor. (2.25 pounds more for the 150L vs the 120).
Soon, I will start my build thread of the MX2.