Accelerator pump operation on an AVS

[Sixt8Chrgr]

I have a stumble off of idle and have rebuilt the original AVS carb on my 69 RT.  I have adjusted the air fuel limiters best I can per published specs. The engine is stock and original to the car except for a goofy cam that was installed. I have no idea of the specs. It has a very lopey idle and comes alive at about 1500 rpm. The timing is 15* at 900 rpm in park. I don't know what the total timing is. I need to check that. The vacuum is 6" at 900 rpm. I realize this timing may be high but it seems to run better with this much timing. I usually don't get any spark knock, but just recently have noticed some spark knock. I believe it is fuel related. I generally run 93 octane ethanol free.
When I look in the carb at the accelerator squirters and give the car a little gas I don't see any squirt from the squirters. The only time I see any fuel from the top of the carb or squirters is when I am at wide open. This seems backwards to me?
Any advice is appreciated.

Lawrence

[myk]

Your timing isn't that high to me.  I'm running 24* initial right now.  I've been told by Ron and others that you have to give your engine the timing it wants, not what you think it needs.  They also taught me that before you mess with the carb you have to get your timing set properly.  It's my understanding that the more wild a cam the more initial timing an engine will need. You should hook up a vacuum gauge and advance the timing until the RPM's stop advancing; that will be your ideal initial.  Then get the remaining mechanical to have a total of 34-39* of timing by 2500-3000 RPM...

[John_Kunkel]

Lazy pump action is the main reason I dislike the A series Carter carbs. Remember, the AVS is an emissions carb, so the idle mixture is on the lean side. Running the idle mixture a little over-rich usually cures most of the stumble.

If you want to go deeper into the carb, remove a primary booster (venturi cluster) and notice the two brass tubes that extend from the bottom of the booster...one is a larger perforated tube and the smaller tube is pinched down near the end of the tube. Using a micro miniature drill set and a pin vise, enlarge the hole in the bottom of the small tube a couple of drill sizes. This will richen the off-idle fuel mixture.

[Sixt8Chrgr]

John,

Any thoughts on increasing the timing due to the non stock cam?

Second choice is to put a Holley 750 CFM on it and see what happens then.

Thoughts?