Be very careful with HP numbers. My old (40 years+) sears compressor has a 2 HP motor on it. A later model has a 3HP motor on it. If you look at the amperage rating they both draw the same amount. I think the MFG's are taking the starting amps, which is quite high, and using it to skew the number upwards. Look at the "running" amps for the true tale.
CFM and max pressure are really what you need to look at on a compressor.
Ken
