Jim, here is a side by side of an early .80 and an .82, the early on the left has 15.5 to 1 compression and now wears C&H Ignition set at 32 btdc, 35 degrees was not quite doable with the high compression. I don't remember the .82 numbers and don't currently have an .82. The .80 is from the late 80's and is still all stock with many hours.