by big bill
These 147's used the starter/generator's so the knotch in the pic is ok. I believe the geared flywheels/starters need even more width in the frame too. My point is it matters if we use a s/g or geared setup too.
They knotch out the frame and leave very little vertical part of the frame as being structural sound. If i was going to design a cut out like this I would put a "U" shape gusset around that area. Thats been my plan if i ever knotched the frame for a larger engine.
The geared flywheel/starters use the same flywheel shroud/bearing plate as a starter generator do with two exceptions-there has to be an place for the starter gear to go and the stator must be able to mount to the bearing plate.
You need to look a little closer at Jim T's pictures. There are gussets on the frame. There is no need to have an U shape type gusset where the wings are. The gussets that IH used are good enough to handle any power that is in the Cub Cadet. That is the same modification the pulling guys do to their Cubs. There is no need to over kill-over engineer the Cub Cadet frame.
A 16 horsepower Kohler will fit in your Cub Cadet if it is the narrow base block and if you modify the frame. I've heard of some that used a flywheel-bearing plate and flywheel shroud off a 12 horse power Kohler. There could be some cooling problems with this modification. A wide base block can be modified to be a narrow base block....The block will need modified to work.