Most of the leak down meters I've seen and used call for 80 lbs., not 100
My air compressor kicks on at 75 lbs. and shuts off at 125 lbs. so when it kicks on so I have wait until it shuts off to continue testing
I set the pressure on every cylinder to make sure I'm getting semi accurate results, you can rock the crankshaft a couple of degrees with air pressure in the cylinders, not to many degree though and see a change, especially on a cold motor