Reply to "Did new ac system instead of Atomic throttle body fuel injection"

That sounds like a mild build, which should be good with the basic tune that the Atomic unit would have. You might want to watch your fuel air ratio because sometimes a built up engine wants a bit of a richer fuel mixture than a stock or very mild build. If you feel it leaning out at certain speeds, you might have to richen it up a bit. The last thing you want to do is have your engine going lean because that can lead to damage. I found that out with my EFI system when I was at lower elevations and at about 2600 rpm in 5th gear. My engine didn't like the operating around 14:0 to 1 ratio, but dropping down to a bit took care of the problem. Of course, I am running a somewhat radical built.