I have had nothing but problems with distributors, I purchased a Mallory HEI distributor, but I could not get it to work right at all, (previously posted) so I returned it. So I decided I would spring for the best so I bought the MSD Pro-Billet HEI 8365. I got this one to run, but my problem is that I can't get it run right. Timing is an issue. I get it to run ok if I have it all the way advanced. This can't be right. I changed the springs in it to see if the advance curve might affect it, but i think all it did was cause the rotor to arch caused it to scorch on the terminals. Does the centrifugal advance have anything to do with it? The old distributor worked without advancing, the car is an 84 Grand Prix Chevy 305. The old dist. had a connection I believe for the knock sensor, but that shouldn't have anything to do with it. Any help would be beyond appreciated....