I saw this posted on the Diablo forum:

The results will shock alot of you but I cannot stress enough that this is on a completely stock car. With that being said, do not run the Perf 93 Tune in a stock challenger... This forum will not let me upload JPG files but here is the results!

Results are as follows:
Stock : 350.81 rwhp / 344.80 ft/lbs
Perf 91 Tune: 360.28 rwhp / 361.49 ft/lbs
Perf 93 Tune: 348.19 rwhp / 348.05 ft/lbs

Can anyone on here confirm this? I have a CAI and the Diablo and I'm quite happy with it. I'm currently running the 93 tune w/ CAI, so I want to know if I should change that to 91 tune. Anyway, if you have any information, I'm interested.

 

The 93 tune assumes a CAI. If this was a bone stock car I could only guess that the CAI was needed, or the gas used was not up to par.