Idle afr with cam and LT's

[streetlegal]

Is there no way to get an accurate lambda at idle with Lt's and a cam. Car in question is a 01 TA with a 408 with L92's and a small 226 int dur cam on 117 lobe sep. Car lopes around a lot at stoich but if I move the lambda around to get the best map and lowest IAC counts it idles stock and smooth. The owner wants it to idle stock. To get the smooth idle my WB is at .88 lambda. I can leave it that way at idle up to 1200 rpm but then I get this lean spike on light acceleration when it goes into closed loop above 1200 rpm and pulls too much fuel out. I guess I can fix that by playing with the switching points. Would you advise leaving this thing at .88 lambda(if thats even accurate) at idle? Do you advise tuning idle this way at all? This is new to me as most of my customers actually want the rough idle.

[SultanHassanMasTuning]

check your timing at idle and post tune & log so we can assist

[streetlegal]

Ill check timing at idle. Its low and the idle and main spark tables are matched up. Ive been up and down on the timing with no improvement.
I'll post a tune when I get back to that laptop.
I'm mostly just wondering if the method I am using to tune afr at idle is appropiate to get the smoothest idle. In my experience tuning big block cars with dominator carbs, I adjust idle mixture screws and the closer you get to proper fueling the higher it idles because it is now running more efficent. I then have to idle them down. Im just using that method here looking at the IAC counts. My counts are up around 100 at stioch according to the wb but when I fatten it up to .88 or so lambda the IAC counts drop to around 60. Map is obviously improved as well.