Seems like there was a thread on here about that a while back. As I recall the guy just wanted to remove condensation from his alky motor and it worked fine for that, but didn't pull enough vacuum for anything else. Personally, I would'nt spend the money on a vacuum pump for an engine that small, especially if you're searching for a power/et gain. Much more cost affective power gains to be had elsewhere.
Even on the big inch engines, the power increase doesn't amount to much if any et gain, but that's usually not the point...
Johnny