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I plugged the vacuum hose and set timing to the timing mark (10degree) and got the dist set with the motor at tdc. It started right up and the timing light showed it still at 10 degree. I adjusted it slightly to run better. I turned it off and hooked the vacuum hose back up and it started right up but was negative (I think, it turned approx 30 degrees counter clock) 30ish degrees. It was running fast so I turned it back to approx 10 with the vacuum hooked up.
Is this right? It's running fine so I figured it was but I thought if you set it with the vacuum hose plugged that was where it was suppose to be.
Fixed it. Vacuum was hooked up to the rear intake vacuum port when I bought this truck so thats how I've alway run it. Called Edelbrock about the 1406 carb I have and they said the vacuum line should be hooked up to the passenger side port. Runs perfect now.
You initially had it connected to manifold vacuum, and have now moved it to ported vacuum. Ported vacuum is widely considered "correct", but there is something to be said of running it on manifold vacuum. Ported essentially IS manifold vacuum, except at idle, where it has no vacuum.
Having it on manifold can really improve idle quality. I've used both methods, and on some I've found that I prefer it on manifold. You can try it either way.
Regardless of which port you use, do set it with out the vacuum hose connected. If you use the manifold vacuum port, don't be alarmed at the added advance from the vacuum advance afterward. When you step on the gas, vacuum will drop, and you will likely be back to your initial/mechanical advance curve.