ok... I'd not recommend this if you do not have a firewall between you and your engine, and the money to buy a new engine if it pops, (superchargers and turbos can eventually do so if you go nuts with the PSI's) you can supercharge/turbo (turbo requires 2 mounted back to back and hooked into exhaust) a normal cart engne for not alot of money if you have some tool and brain power. for a 3-6 hp I'd say out of an older 4 cyclinder would probably be big enough. your only going to get 1-2 psi in most cases, but it will be a noticeable difference and if your motor is taken care of shouldn't be outside the range of your carbs adjustments. I've SEEN this hooked up and it does work, now, it does not perform like a $1400 5+ psi bike turbo, but it works and seat of pants is quite noticeable on small engine (its not going to turn a 5 into a 50 hp, but a 5 into 8 would be within reasonable). I prefer the supercharge (costs less, belt drive it with a secondary pulley or chain, may require use of a jackshaft and/or motor movement depending on engine shaft length. which is where the turbo may be easier, but IMO it won't last as long, and will be harder to regulate PSI using a Blow off valve(if you use a BOV PLEASE use 2 or 3 all set to the same. if one starts sticking, you could end up in a bad deal if your pump is really putting out 5+ psi as these small engines can break apart (hence firewall advisory and me liking superchargers)
another neat idea about the supercharger, would be use a 12 volt electric clutch (A/c or lawn mower blade engager could be source) you could turn it on for short periods and use it like NOS at a higher PSI/flow. this would create a lean condition in the engine, which for long periods would be bad, but it would spin up like it does when it runs out of gas, except it won't run out of gas!
the reason this works is simple, if you can get more air and fuel pumped in, performance will increase, you already know this...... but even 2 psi though it sounds like nothing, is alot if you consider the carb was creating a vacuum just to run and now its not, that will increase RPMS and available power by decreased load.
