That sure explains a big pump bogging down a small engine.
True, to an extent. A16 gpm pump on a splitter with 1/2" lines will likely bog a typical 160 cc flathead "5.5 hp" engine, just dry cycling the ram, before even putting any wood on the beam. The op has 190cc OHV, which will almost certainly be more up to the task, and it amuses me that both are rated 5.5 hp (if true).
I've never looked at electric splitters, at all. But for torque and cost, I assume they're using universal motors, which have a peak torque to rated horsepower ratio much higher than any gasoline engine. Their torque also doesn't follow the same curve, having more of an ideal hp/5252 rpm trend. I wouldn't expect a 3 hp gasoline engine to do very well at 11 gpm, lacking sufficient torque to keep the RPM's up in the power band, but it's likely no big deal for a universal motor.
All 3 hp motors are "real", but the method of measurement and the usefulness of result for a given application varies. Universal motors are often measured by stall current. It's as real as anything else, for knowing how much torque and power the thing can produce prior to stalling, but obviously produces a much different result than a split-phase induction motor measured at 5% slip. Of course, with the exception of a repulsion-induction motor (which is really a universal motor coupled to a regular induction motor), most induction motors have very poor start-up torque. RI motors are usually more expensive, heavier, and larger than other (eg. split phase) induction motors, so I'd think them to be a poor choice for a log splitter, but perhaps someone is using them.
