During a recent 12,500 mile tune-up on my 1978 BMW 320i, I had done everything in accordance with the factory manual except the ignition timing which I advanced by rotating the distributor counterclockwise 1/8″ by the marks between the center of the rotor finger and the line on the distributor housing. In other words, the center of the rotor finger is 1/8″ (clockwise) ahead of the line on the distributor housing while the pointer and the notch on the crankshaft pulley were exactly aligned. The result was an impressive gain in engine power. I fully realized that this deviation does not meet smog regulations but I am more concerned about any harm to the engine in the long run.
Author: Richard Ting
Not knowing where the distributor was to start with, it is hard to say what you have done. Perhaps the timing is now exactly right, having been incorrect before. How do you know there is more power? Assuming you did not put the car on a dynometer, running the stoplight grand prix will give you only a subjective feel for any difference in performance. Without a timing light in your hand, you should not mess with the timing You could find yourself looking at a hole in the top of a piston. Tech Ed