by Ed Esslinger in the January 1998 RootesReview
After installing an ignitor module in my Series V distributor, I noticed an interference problem between the rotor and the ignitor case. I didn’t find this problem on two previous installations. Further investigation found there are two different rotors used in the Alpine distributor. One has a short output blade, and the other has a long curved output blade and a step at the back side that interferes with the module. The solution to this problem is to file a small amount from the step to clear the module or to use the short blade rotor.
Does anyone know the reason for the long curved rotor? I have used both types with no difference in performance.