I don't know how I had 12.5 at idle as I mentioned earlier. I may not of had it up to temp or something.
Seems reasonable.
First, vacuum at idle is at 15 after that it goes up to around 22 at 2,500 to 3,000 rpm.
Here's what my A/F gauge is telling me:
800: 11.5 (To make sure I was on the idle circuit)
1000: 11.4
1300: 10.9
1500: 10.6
2000: 10.5
2500: 10.6
Presumably this is in gear, driving at steady speeds.
Tracking this as you have started is a good way to help tune the idle circuit.
For it to idle around 950, my idle speed screw is turned in 1 1/2 turns. I don't know how far into the transition slot that puts it.
Tip. Next time the carb is off, measure the transition slot visible for every 1/4 turn in of that screw. Now you'll aways know. If you can, measure the t-slots length and width as well for future reference.
The transition slot visible at idle should be between .020 to .040"
I don't know if the carb has replaceable idle jets or not.
Probably not and they're probably in the wrong place anyway. Tap and relocate as explained in the link.
I plan to pull the fuel bowl so I can note what main jets and power valve are installed so I can look and see then.
The PV and MJ can be looked up the on Holley's list Numerical list. Links to it in the Holley Stickies.
The carb is a 950 street HP so it doesn't have the adjustable idle air bypass screw like the ultra models.
No biggy. IF needed, you can make your own or drill the throttle plates. The former is convenient to adjust, the latter provides better mixing of the fuel into the airstream.
I bought a calibration kit that has jets, power valves, squirters and gaskets. I also bought some air bleeds.
Great! To find out what size bleeds the carb has now, you will have to measure. For this you'll need micro-bits or gages. Bits are cheaper and can be used for drilling your own bleeds and feeds if needed. Then take the blocks off and map it all out. Many of the new carbs have three or more "emmulsion bleeds". Using just two tends to produce a better, more consistant flow. However this shouldn't effect your idle circuit tuning.
As far as timing goes, my initial is at 14 and all in around 3,000 if I remember correctly. I will confirm that.
That is a good idea. Plot the timing from idle until it flattens stops advancing. Intial timing seems a bit low on for that engine and cam. Barry Grant used to have a chart on-line for selecting carbs that also had intial recommendations. Try between 16 to 20 and it should be able to idle with less throttle opening. (This assumes no vacuum advance at idle)
Tip. Keep note of how much the idle mixture screws are open.
Tip. Make sure to check the fuel level in the bowls. Old style starting points is just at bottom of plug. Big window style is usually mid-window, but follow whatever instructions say.
Then I will start with idle and work my way up like Andy mentioned.
Remember, the name "Idle Circuit" is misleading. The car will be cruising 40 or even 50 mph on the idle circuit.
edit: I agree with Andy on check the spark plugs. Always see what they can tell about what is actually happening inside.
I disagree on the idle AFR. Depending on cam, it may be more efficient and powerful down around 13:1 Even many production cars ran best with richer than stoich idle (through the late '60s for some non-CAP vehicles). See the AFR - Load graphs in my earlier link.
