Sorry this is so long.......

Ok, so here is the back story. I'm working on my 86 D100 pickup, stock 318/auto, 2bbl. This truck had the Electronic Spark Control computer mounted under the fender, behind the battery. I'm not sure if this computer qualifies as a lean burn or not, but all it really did was control spark timing. As with the lean burn mounted to the air cleaners of the cars, the "vacuum advance" was attached to the computer. Now I've been told that this wasn't actually a vacuum advance, but more of a map sensor. Whatever it was, when I plugged in the vacuum hose, the timing changed. The hose, plugged into it's original location on the carb, did have full time vacuum.

Well, I eliminated the computer system by swapping in a "ready-to-run" distributor I got off ebay. It's one of those dist. with the built in modules. All I needed to hook it up is a power wire to the coil and two wires from the coil to the dist.

I've gotta say, this was probably the best thing I've done on the truck so far. It runs so much smoother. The only thing is, I'm not sure how to hook up the vacuum advance. It's my understanding that the advance should be hooked up to ported vacuum, not full time vacuum. But the original "advance" was hooked up to full time.

I only have two vacuum ports on my stock Holley (Carter BBD designed, Holley built) 2 barrel carb. One port was hooked to the original advance, the other port connects to a thermal-vacuum switch, which then connects to the EGR. But this port does not seem to have any vacuum at the carb, even when I open the throttle. Does it have vacuum when under a load?

I guess my question is, should I leave the vacuum advance disconnected? Should I hook it up to the full time vacuum? Should I hook it up to the other vacuum port and leave the EGR disconnected? What would be best for the best fuel milage and throttle response? Right now, I'm driving the truck about 150 miles a day on the highway and I'm getting about 14 mpg. I'd like to do better if I could.

Also, my throttle rsponse, although not entirely perfect, seemed to be better with this new distributor than it was with the old computer. I have been driving it with the vacuum disconnected for about a month (the 14 mpg was with the vacuum disconnected) and throttle response has been fairly good. I like to step on the gas and go, not stumble around coughing and wheezing. Out of curiousity I guess, I hooked up the advance to the full time vacuum. I don't know if there is any improvement in milage yet, but throttle response, especially when cold, sucked. My initial timing is set about 9 degrees. I have no idea where it's at with the vacuum connected. I don't have a timing light (borrowed one for intitial settings, can't do that now). Anybody have any advice at all?

One last thing, the carb is NOT a feedback carb. Just because I originally had a computer does not mean I had a feedback carb. There are no wires going to this carb other than for the idle solenoid. Also, swapping this carb for anything else is out of the question. Yes, I would love to swap in a four barrel on an eddy manifold, but I have no money. Even swapping this carb for an older version is out because, again, I have no money. I just want to know what my best option is: leave the advance disconnected, connect it to the full time vacuum, or connect it to the other port. And what would be the effects of each option?

Thanks...