Cliff's Quadrajet Parts and Rebuild Kits

Finally got time to respond. I mentioned the 12HG spring as the engine, IMHO makes low vacuum. My Vac gauge shows 12-12.5 Hg and who know how "accurate" it is. So I believe that maybe the spring was pushing the rods up a tiny bit. At the same time very black water was dripping out the tailpipes. It was nasty.  I made two changes at the same time. Went with Cliffs black spring and 48 rods.
This car has very low static compression at 120PSI all within 1–2 lbs. This car is a survivor unicorn.
Lived in a dry garage its whole life and stopped being driven in1978, then from 78 to 82 summers only after that to 93 only driven once to the PA inspection station for a new sticker. I thought it important you knew something about the engine. Perhaps with time and some miles the compression will come back up, and I'll get better combustion action.                                        So with 74-48 and black spring combo.
Getting cold start 1st step down 13.2ish, warmed up idle A/F 14.3-14.6ish 40mph 15.2-15.8ish 60 mph pretty much the same as 40 WOT 11.5 then it comes up to around 12. And moved the Acc pump rod to the back hole. That alone made the engine much happier right off idle. But maybe it's not getting enough pump shot at tip in? I have to drive it more and watch the AF gauge.

These changes have made it more enjoyable to drive and no more soot black condensation puddles on the garage floor or choking clouds of fumes.

Not crazy about drilling bigger passages that is too permanent for me with this car. I think I have pretty good control over the idle screws? Maybe more experimentation is required? Haha. What's a good test for that please.                                                                                                                  All I want is a nice driving experience with minimum fuss. Converting over to electric choke since I have blocked off the intake/carb heat crossover. And need the high idle to step down faster.

The needle moves according to the speed of the centrifugal control turning, then you see the number of degrees on the scale per speed you are using.

 Well, I have a problem that is stumping me, I need some advice.

 Here's the situation.  I have my test distributor set up just like the one in the picture on page 1 of this thread, and it works very well, my timing light is going off at a minimum rpm of 400, which I think is fine, that allows me to pinpoint the degree at which it fires.
 
 Here's the problem, as I speed up the drill and it reaches 2500 rpm distributor speed, the light shows that the weights are deploying to maximum at around 1000 rpm, ( I have light springs on it just for initial testing).
 However, the tip of my timing indicator that is substituting for the rotor shows that im only getting around 4 degrees of advance. And I was getting a strange second flash from the timing light, you could see it on the distributor shaft and weights, like a double image.

 At first I thought I used the wrong pole piece, it was a 6 cylinder one with 5 of the points ground off, but it had some really odd shaped sections to it, so I switched to a standard 6 cylinder pole piece that looks identical to the 8 cylinder one, just 2 less points, then removed 5 of them. Works exactly the same, lights up the timing light at 400 rpm all the way up to 2500 rpm. This eliminated the second flash and double image, but I'm still not showing any more than 4 degrees of advance, even though you can clearly see the weights are extending completely.
 The center plate is a #482, and the weights are a #105, with just the lightest springs I have.

 I also thought that it might be the aluminum reinforcement plate I installed to keep the protractor steady, causing some weird interference with the pole piece somehow,  so I removed it and checked again, same result.

 I swapped the capacitor in the distributor as well, just in case, same as before.

 I took an old plastic rotor and ground it off on the bottom to clear everything, marked where the firing point is, and it still only shows 4 degrees of advance.

 Anyone have any ideas as to what would cause this? I'm at a loss now. I'll post pictures on the next post for reference.

 Rick

update...weird sh!t and im a dumb@ss.
woke the boat up for this season, added vacuum gauge and took it out 2 weeks ago.  ran 21p prop.  plane times are down (around 5s or so) and still bogging at wot.  cruise seems great, 3200-3400, but gauge is showing steady 7".  wot showed 0", so i tightened the air door spring from 1/2 to ~7/8, then 1-1/4 turn.  this did nothing.
removed carb that night and checked it.  somehow, the spring came off the air door and was wedging against the rod it's supposed to hook on.  when secondaries opened, there was enough vacuum to flop the air doors fully open, and the vacuum break would close them when i cut throttle.  after i found this (on the bench), i tried for almost an hour to recreate it so i could get pics/video of it, but had no luck.
reset spring to 7/8 turn and put in DG rods with an L hangar.  top of air horn to center of hangar holes was set to 0.64" +/- 0.01" or so (hard to see at an angle). 
checked idle mix and found they were 5 turns out, so warmed up engine and rechecked using vacuum gauge.  settled on best vacuum at 19" and 3.5/3.6 turns out.
took boat out saturday for another run.  put 23p on for snits/giggles.  plane times still low, cruise was smooth at 3200/3300 with 7" vacuum and ~35mph (guessed...didn't actually check).
wot still bogs, but now backfires thru exhaust (that sht sounds weird as hell in a boat).  vacuum at wot was showing 1-2".   played contortionist to loosen air door spring to ~5/8-3/4 turn or so and put 21p prop on.  plane times still >5s, vacuum at 3300 still around 7", wot now showing 0-1" vacuum and bogging but no popping. 
got aggravated and went home after an hour or so.   weather was great, lake was smooth, but not much room to adjust what i need to with everything installed.  cant watch carb while driving, either, so been playing the guess/test/cuss game.  did not check speed or rpm; was more focused on vacuum gauge.
get home and pull carb again.  this time, open it up to see what's going on.
damn...i had 39b rods with those 67 jets this whole time (since last year).   i coulda swore i put the  36b rods in there.  had to get out the big magnifier to see those little stamps.
changed to 69 jets and kept 39b rods. 
set secondary side to DR rods with a V hanger.  i don't know what's more important on secondary rods...sitting completely down when closed (rods bottomed out in jets), or holding that 0.641" when open.  since this lil 4.3 will never open the secondary side completely (maxing around 40%), i opted for completely down when air doors are closed.  this combo has ~ 0.70"  from top of air horn to center of holes.

i have (what appears to be) the blue power spring from cliff's marine kit.  it seems to be a 'medium' spring, compared to others i have.

also, while i had it on the bench, i measured the MAB at 0.051".  they dont appear to have been molested but are brass inserts.  the IAB are the same on all counts.

so, the questions i have now are these...
is 7" manifold vacuum ok at cruise?  i expected it be more like 10-12", but have not seen any references for 3200-3300 cruise rpms.
is the blue spring ok for this?  searching shows any "blue" qjet power springs are for 9-12", in which case this would run with full enrichment at cruise.
should secondary rods be completely seated in jets when air doors are closed?
if not, how important is that 41/64" dimension when the air doors will never be completely opened?

thanks for reading.

I'd go up more on the timing.