Shaft to gear.

Here's where you can see how a windowed block is necessary to perform this kind of hack job. The cam must remain perfectly aligned in the block. Here you see I'm welding the 5hp shaft onto the 3.5hp gear and keeping it in perfect alignment. The lobe centerline in relation to the gear must be kept for proper valve timing. The Briggs cam gives off easy to read visible cues. I use a stock cam to compare the lobe lift centerline with the casting seam on the gear.