A 4 degree off set key is not an exact amount! It completely depends on the diameter of the shaft that it's used on! For example the MrGasket key part # 988G (see picture and applications in post 176) may be used on a small block chev crank with a snout diameter of 1.2510, take the 988G key and measure the step, it's .050 thou, convert that into "radians", you get .079936, multiply that by 180 and divide by pi= you get 4.5799 degrees. Now stuff that same 988G on a mopar cam snout with a diameter of 1.0625 thou and final answer is 5.3925 degrees! Now double that (2-1 drive ratio to get crankshaft degrees instead) and you can see how that stupid little key amplified the change to end up with a posable 10.785 degree of change in your cam timing!