Stop in for a cup of coffee

Didn't mean to log in but had to stop the incoming e-mail alerts from an chatty conversation.
Limited connectivity here, and just running on battery power.
71GSSDemon said
So Seth's car has made even more confused. Turn the idle extra screws all the way in and it does nothing different. Can't find a vacuum leak something, isn't right. Also there is full vacuum on ported port also. WTF! Has 13" vacuum at idle. So, I am wondering if getting enough fuel in carb somewhere to run and that is picking the vacuum up?? Maybe actually has low idle vacuum and the springs are allowing it to run pig rich picking idle up? This is Eddy AVS2. Going to a Holley I have tomorrow.
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In my experience vac leak is pretty rare.

Agree- if the spark port is showing the same vacuum as manifold, then the throttles are too far open. Back off on the throttles and bring the rpms up by other means. Repeat as needed until the ported vac drops off - prferably to zero.
Increase initial timing (the actual inital you may have to work toward as its probabling idling too high to be on the actual initial).
Let more air in another way (drilled throttle plates are an example of this but not the one to start with).

Turning the idle mix screws all the way in and nothing happens also proves the throttles are too open. All fuel is coming through the transfer ports. AVS2 is a Carter copy so it has a little more sophisticated idle circuit but I dont think that should effect the tuning approach.
71GSSDemon said
Just what I tagged you and Matt @Mattax in last night or this AM. So it smokes terribly. It does have 13" of vacuum at idle, but on both ported and manifold vacuum ports. Guessing the throttle blades are too far open. The idle mixtures screws do nothing, even all the way in, runs fine. Again throttle blades open too far and allowing transfer slot fuel? IDK. Thoughts this AM pointed to maybe damaged the valley pan gasket - this could be an internal vacuum leak and the oil vapor/smoke. Also, the vacuum line that runs from the intake to the transmission vacuum modulator is a known source of smoke. If the diaphragm failed, engine vacuum can pull trans fluid (Not Bud Light @memike has a case though) into the intake near #4 cylinder. This could explain the smoke on passenger side. Plan is as follows:

  1. Change carb to the Holley and try
  2. Unplug the transmission vacuum hose – maybe a diaphragm is bad and possibly pulling fluid up???
  3. Pull oil fill cap and see if there is a vacuum vs blow by – this would prove a crankcase vacuum leak
  4. Pull and replace the valley pan
  5. Reassemble and retest
  6. Then if runs correctly, decide if it still needs the converter or return it
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I dont know that Holley is magic, but any known good carb should transfer over and ran just about as good on another engine.

The other tests seem reasonable if you think its sucking tranmission fluidand can then confirm or disprove it.