1981 non-Turbo 4 cylinder, mileage unknown. I'm hoping to get some help analyzing my compression tests results. All tests were done with the engine warm, the throttle wide open, and the #1 coil wire disconnected. I removed the plugs the day before and then I ran the engine the next day to get rid of any carbon that might have broken free when loosening the plugs.

Testing each cylinder until the gauge stopped rising, all four cylinders are within five pounds of 200. This sounds way too high to me.?. What does this mean?

Testing each cylinder for exactly four ""puffs" or compression strokes, I get right about 115 on all four cylinders on the first compression stroke, and 180-185 on the fourth compression stroke.

It all sounds nice and even to me, but I know there is more to be learned about my engine from these results. Can I assume from these numbers that compression is not the cause of my rough idle? Do the high numbers have anything to do with the fact that I have to run premium gas in hot summer weather (95-100 degress)to keep the engine from pinging? I'm wondering if the pistons might be covered with a thick layer of carbon, raising the compression of the engine over what it's supposed to be. I need some help figuring out what the numbers indicate.
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Thanks to everyone for the help, Doug C. 81 242 Brick Off Blocks, stock, M46; 86 240, 133k