Sorry, I guess I just felt a little piled on. :)
The car ran fine for a few months with timing set right where it is. Then started acting up. Something had changed besides the initial timing, causing the issue. We did try more initial back when I started the thread, and it would just die.
It was pointed out earlier in this thread that the Pertronix might be at fault, which was in the distributor when I bought the car. I know nothing about them, but after doing some research on this site found they act up sometimes.
Yes, I like to do everything myself, but I have work to do on three of my old cars this winter, so threw in the towel on this one, and sent the distributor out.

Could be a bad tank of gas even. Maybe drain it, and dump 5 gal of fresh in there.

Wouldn't be the first time that's happened to me. I'm in a new area and learning where to buy acceptable gas. Older stations and older looking pumps are ones I try to stay away from. But even then, it can be a crap shoot.

I bought 93 at a Sunoco close to me, it has newer pumps, but guess not many use the 93. I pulled my plugs after running it and they had what looks like 'snow' covering the whole plug that extends into the chamber. Obviously, additives, and could be because it had sat a long time and they added it, or it was added by the distributor.

But I had rough idling and det when running it. That's why I had looked at the plugs to begin with.

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The idle issue is probably some varnish that got stuck in an idle tube. Probably nothing to do with the distributer.

The full throttle pinging issue is likely from an issue in the distributer.

I think its worth checking the idle tube as well. I just ran into this recently.

I found a video online to help me out. Found the Idle tubes were completely blocked.

OK, I got my distributor back, and put it in today.
The car STILL dies when I drop it in drive, so the idle issue was not the Pertronix. It makes no difference what I set initial timing at, or even idle speed, just like before.
Not a total loss, as there were some issues with the distributor that I posted earlier.
Anyway, I guess it’s time to pull the carb. Like a few mentioned, possibly sucked in a chunk of crap. I changed the filter when I put this Quadrajet on last year, so it must have got past it?
The car ran SO good for about a month or two after I switched to this carb. Ugh

If both of your idle mixture screws when turned either way with the motor out of gear will effect the idle which is as it should be, then I say You have a vacuum leak more likely then not making for your issue.

When doing this check out if you find that one mixture screw needs to be adjusted way different then the other to attain the best idle then you have either found the side of the carb with the issue, or the side of the intake that gets fed from that side of the carb.

What shape is your timing chain in? Maybe it jumped

you can take dist cap off and use a socket on front of crank rotate engine back and forth see how much crank turns before dist. easy peasy

also take a vacum reading it may be drastically off possibly indicating chain jump

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Chain jump would be indicated by a sudden timing change once it started to run badly.

George

Could it possibly be a ruptured diaphram in your power brake booster causing a vacuum leak? And when you push on the brake petal, when you pull it down in gear, it makes it worst, causing it to die.

post #21 isnt real clear on sequence of events and


" Then started acting up. Something had changed besides the initial timing, causing the issue. "

something had changed besides the initial timing? seems like as written the initial timing changed

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We disconnected the booster vacuum line and plugged it. Same with the vacuum line that runs to the transmission.

That was in response to someone saying all I had to do was advance the initial timing to fix the problem, instead of running it close to the factory settings. I played with advancing and retarding the timing from where it is currently ad nauseam.

You sure you got the correct base gasket on there? I know there's a couple diff ones, and the wrong ones cause a vacuum leak.


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Well, it looked correct when I put it on. BUT I have an update.
Put a spare coil from my GTO on. It didn’t die idling in the garage. No time yet to take it on a drive for further testing, but it looks promising. I ordered a new coil anyway, as I have no idea of the origin or age of the one that was on originally, but it’s definitely not stock.

Well anything is possible and that's good news if true, but I have a problem seeing how a coil with low output could fire a rich mixture as when the motor is cold and with the choke on, yet fall short when the motor is warm?

Doesn’t make sense to me either, but had a little time to kill, and figured it wouldn’t cost anything to try a spare.

Could have something cracked internally, opening a circuit when it gets warm.

Spark output drops as a coil heats up.


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