Timing
 

I have a quick question, when using an advanced timing light and you are just trying to check to see if you motor is running at 8 deg what deg should your timing light be on?

Re: Timing
 

If you're using a setback type timing light ,yes.You do need to remove and plug the vacuum line to the dist.Plug the side to carb or manifold.Also you may want to chek the condition of the harmonic balancer.If it's cracked or looks worn it may have slipped giving you a false reading.Someone should be able to give you more info on this.

Re: Timing
 

If you unplug your vacuum advance and plug it off then set your timing light to 8 your timing mark should be on 0. If not turn your distributor until it is, tighten and plug your vacuum line back up to the distributor.