I have a question about A/F readings and a cam

It's not the cam.

The cam in my 340 is 234/242 @ .050" with a 110 LSA and vacuum at idle is ~9". Advance at idle is 22*, all in mechanical is 35*. It will still idle at 14 on the AFR, I run the same Innovate wideband AF gauge too. I run a Holley 750 Ultra DP with mechanical secondaries.