The distance on the plans between the firewall and the prop washer is exactly 5-1/8 inches. The length of the Saito 120S + engine mount is 6 inches. Either I move the firewall or the front of the cowling. Last time I checked, a 6 inch engine will not fit under a 5 inch hood. I would much rather move the firewall than change the basic propeller position.

It doesn't sound like anyone is recommending the 100. I guess I'll stick with the 120.