Here's one..

how does a fellow or a gal determine the compression ratio of a motor?  I've
been thinking to take a reading with my compression tester,  then divide
that by the barometric pressure.  Is that correct?  And what kind of PSI are
people commonly getting from compression tests on various motors?  Does
anyone have any actual numbers scrawled in the back pages of their Bently
books?

  This is in aid of trying to determine the CR of my "new" inline four
'Franken-mouse' motor..with 1.8liter head on top of a 2.0 liter block and a
pretty stout headgasket from a specialty tuning shop..  I am not so sure I
will hear it if it is detonating, way back there and with my magnaflow
exhaust system kinda buzzy.  If my ECU gets "knocking" signals from the
sensor and adjusts the spark back always, I will probably need more octane.
If I know the number I can decide without really guessing too much.

  Don Hanson