The timing should hold steady. I'd check for sloppy distributor bushings (despite the fact that it was a rebuilt part). Also a worn out timing chain/sprockets. It's easy to check the vacuum advance if you have a MityVac hand pump. A distributor tester is really the perfect tool for this troubleshooting but not a lot of shops have them anymore. Heck, a lot of modern cars don't even HAVE distributors. Pete in PA From: "Chris Strohmeyer" <chrisstroh@xxxxxxxxxxx> Subject: IML: distributor timing Date: Mon, 30 Apr 2007 12:14:35 -0700 Reply-To: mailing-list@xxxxxxxxxxxxxxxx Hi all, I need a clarification on timing with a light on my 67 Imperial 440. When at idle with the vacuum advance disconnected I get a steady strobe image on the 6 degree before mark. However, if I rev the motor to a steady say 1500 or there abouts the mark moves but doesn't hold rock steady..it jumps around a little bit about a half an inch. If I hook my advance back up and rev to full advance it advances but doesn't hold steady. Should these readings be ROCK steady or close to rock steady? As some of you probably know, I'm still have an erratic running engine that comes and goes as it pleases. The distributor I replaced from Kragen's (I know I'm going hear it about that) because of this problem but it's still there. A mechanic told me the "new" one could have a bad vacuum advance and or sticking or improper tension advance springs. What should I look for? Thx, Chris Strohmeyer 67 Imperial Convertible ----------------- http://www.imperialclub.com ----------------- This message was sent to you by the Imperial Mailing List. Please reply to mailing-list@xxxxxxxxxxxxxxxx and your response will be shared with everyone. Private messages (and attachments) for the Administrators should be sent to webmaster@xxxxxxxxxxxxxxxx To UN-SUBSCRIBE, go to http://imperialclub.com/unsubscribe.htm