I really only static time, then check with the light to see if anything looks wild. That dial on the distributor works well enough and I figure I'm near 4 degrees. 3/16 sounds tight to me based on my blinking white mark, but I'm not touching a thing because after many years of playing with TR engines, my TR4A is going on one full year of great running plus an incredible anomaly. When I shut off the engine, the engine actually shuts off, completely and quietly, like an old Buick. No need to clutch it down, just fizzles right out. Peace for the Holidays.