Vaccum at idle has always been an indicator of the overall health of the engine as it'll expose anything that lowers the pumping strength of the engine (assuming everything else is within spec). Tight valves, poor piston ring seal, air leaks, even a clogged exhaust system are some examples. Mechanics have used it for years as a tool for tuning. I'm able to tune the timing and AF ratio for best vaccum at my idle of 1000 rpm (which implies the least throttle/IAT opening and best combustion efficiency). If you're winding it out and suddenly lift you should see way more than 22 inches, 25+. Yes, with a timing light you can check it easily, just consult the on-line manual. You might want to check your gauge as well. Also, if you just installed the Comptech S/Cer, check the fuel pressure at idle. Should be about 40 psi. If it's higher, you'll probably be running rich as the ecu isn't in closed loop during idle. That might explain a low vaccum at idle, but it doens't explain the chopped throttle results.