Rich Idle AFR reading
In my opinion, a stock cam 318 is more efficient at low rpm than say a 340 or a 440 A134 and therefore does not need or like too quick of an advance.
My suggestion is slow down the advance. Make it look something closer to the non-CAP 318 timing. Doesn't have to start at 5*, 10* or even 12* would be OK, but the overall shape should be closer to factory non-CAP 2bbl 318, or a 4 bbl 273.
Look at the general AFR curve in this post: Wideband
Basically yes. Highest vacuum at idle (in gear with an automatic) is a good indicator of power. With a manual transmission, just set it a tad richer than leaner because obviously you can't play with the idle in gear.
750 rpm is actually a little higher than stock. The aftermarket intake is the only thing that might make it a little less efficient at idle - and therefore need the slightly higher idle speed.
I see no reason to raise the idle speed.
So here's the deal. The LA 318 was born in the begining of the smog control era. A '69 would have been set to idle at 14.2 AFR with timing around TDC (Dodge) or 5 ATC (Plymouth). In my opinion, for what you are doing - looking for performance - the initial you are using is about as much advance as it probably needs. It should be able to run decently at 600- 650 rpm with as little as 5 BTC (and the AFR closer to 13:1 than 14:1).
In my opinion, a stock cam 318 is more efficient at low rpm than say a 340 or a 440 A134 and therefore does not need or like too quick of an advance.
My suggestion is slow down the advance. Make it look something closer to the non-CAP 318 timing. Doesn't have to start at 5*, 10* or even 12* would be OK, but the overall shape should be closer to factory non-CAP 2bbl 318, or a 4 bbl 273.
