davoaz

My control switch was bypassed when I bought the car. The distributor vacuum house is routed to port in front of the car directly about the right air mixture valve. I was looking for a place to attach a vacuum gage to try and dial in the air mixture and pulled this vac hose to get reading. I noticed at idle there is no vacuum there. Not sure if it pulls vac under a load. Question is, is this a good place to run the dist adv hose or do I need to route somewhere else?

oldcutlass

Your distributor apparently is connected to ported vacuum. It only provides vacuum when you are not in the idle circuit. What you need is a manifold vacuum port. There are a few of them scattered around the intake and where the transmission modulator valve is connected. Hooking the vacuum advance to ported or manifold vacuum is a personal preference.

joe_padavano

The ported vs. manifold vacuum debate has been going on about as long as there have been cars with vacuum advance. Since the gasoline available today is not the same as the gasoline these cars were designed to run on, use the one that allows the car to run the best. Be aware, however, that ported vacuum (ie, no advance at idle) can cause overheating in stop-and-go traffic. This is why the factory used a thermo vacuum switch on cars with ported vacuum to switch to straight manifold vacuum and advance the timing if the car started to overheat. By bypassing the TVS, you have lost this fail-safe function.