Well, I guess I should probably chime in here. I work for Briggs and Stratton so I think this is pretty sweet. Those are actually Vanguard V-twin, the commercial brand of Briggs and Stratton. The problem with the engines are they are governed to 3600rpm, so they may only put out 18hp but that's at 3600rpm. Just by eliminating the governing, assuming an aftermarket cam, you can get 25hp out of it. Now there are a lot of factors such as floating the valves and other things, but if he did it right those engines can put out big hp. We have one that has been dyno'd at 72hp. It's a pretty cool project, but I will agree that it going to be a dog. Plus with the engines being air cooled, I am pretty sure they will be getting mighty hot in the engine compartment, especially with two of them in there.