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Building engine mount


Well-Known Member
Sep 1, 2006
Reaction score
Ok---I've hit a snag.

Started building a jig for a new engine mount (Starduster Too, O-320-B, conical mount, 26 inches from firewall to face of mounts). Have the firewall end of things done---now gotta get the mount points for the bisquits of the mount in the right place. Have confused myself to the point that I'm asking for help to get thru this.

I understand that the center of the prop flange needs to be on the centerline of the plane, 6 inches below the mount spools centerline. The rear of the engine needs to be offset to make the thrustline 1 1/2 degrees right and 1 1/2 degrees down. How do I figure this out?

Was thinking of making a "dummy" engine---mountpoints and shaft for centerline of crank---use that to set the offset and drop, then build jig off the rear to join with the jig from the firewall forward.


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