- knows what a master orifice is and how to use it
I saw what you did there: a trick criterion.
Anyone who knows about piston aero engines knows that master orifices are scrap metal used to raise money to buy a boroscope!
A quote from a thread from another blog that's on point:
My mechanic calls [compression test results] "buyer's numbers" and "seller's numbers" as he manipulates the prop to show either 45/80 or 75/80.
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