Need help with timing for a 250 inline 6

I was timing the engine and was wondering if before I time it do I need to have the vacuum advance on the distributor disconnected while setting it. It's a 1973 250ci inline 6.

 

Yes, you need to disconnect the vacuum advance and plug the hose. Than you can time it at 6 degree TDC.

 

The specs say it should be 12 degrees for a 250 inline 6

 

Your right. I was going on memory bad idea.

 

Set the timing where it runs the best. I would use a vacuum gauge instead of timing light