[neutron256]

I did some searching on ebay yesterday for supercharger options. I found an interesting supercharger for SeaDoo 4-tec engines. The gearing is integrated into the engine but the compressor itself is designed with a large wheel designed to turn at slower speeds than compressors from turbos.

I couldn't find any compressor maps but after some digging and some math it looks like on a 1.8L engine they produce about 14psi at 8100 RPM. The gear ratio works out to be about 43k RPM on the compressor wheel.

I wouldn't expect to get anywhere near 14psi, but that lends to much more reasonable motor speeds for a direct drive from the motor. Also the larger wheel gives me more options when it comes to coupling the compressor wheel to the motor shaft.

I went ahead and ordered a used SeaDoo compressor to experiment with. There seem to be a lot of thes on eBay. The bearings/clutch setup frequently needs to be rebuilt probably due to operating in a marine environment. But as long as the wheel hasn't contacted the housing I don't really need the bearing/clutch portion working.