Briggs & Stratton Vanguard 23hp build


Well-Known Member
Supporting Member
Feb 12, 2013
OK, starting a thread for my engine conversion. I just purchased a Vanguard 23hp engine. (386447 series) The goal is to minimize weight and maximize -reliable- horsepower. This will be a direct drive installation, so I do not forsee pushing the engine much past 4,000 rpm. Looking for incremental improvements. No billet spark plugs!

I will be mounting the prop on the flywheel end, because.. that's what Briggs (Europe) did on the ULTRA UAV. Since I won't need the PTO end, I was able to save some money by getting a 'generator' model with the internal spline PTO. I also bought an oil pan/engine cover from a vertical shaft engine so I can 'more directly' mount the engine to the firewall, rather than using a bed-mount engine installation.

But first is getting some base line info on the engine. So unless I can find someone with a dyno, I will be building some Eiffel clubs.

See attached photos of the engine.


  • 386447.jpg
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  • 386447 - PTO end.jpg
    386447 - PTO end.jpg
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