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Allan,
You didn't miss much! Just be sure to hold the throttle wide open while cranking. Sometimes you need an assistant, as it usually requires three or four hands to do everything at once, and watch the gauge, too! I would expect compression numbers in the 150 to 200 range for a 9.1:1 engine.
As far as the leakdown numbers go, those are just the raw numbers off the gauge. But, quite good , I should say. The 'normal' practice is to subtract them from 100 psi, the regulated input pressure, which would yield values from 3 to 6%. A leakdown test doesn't tell you much by itself. Combined with compression numbers, they can be useful to troubleshoot problems with rings, intake, or exhaust valves prior to making a rebuild/refresh decision. You must listen at the tailpipe, intake air horn, breather tube, and underneath the engine ... to decide whether leakage is occuring past an exhaust valve, intake valve, rings, or cylinder/head junction.
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Warren Hall
1973 911S Targa
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