Updated and now my car shuts off when i idle too long..

[MuscleMan305]

I have the 5.7 with no mods except removed the suitcase muffler. I updated to 16b (the latest one) and used 93 oct perf tune with firmer shifts.
Do i need to raise the fuel or idle?? it idles around 525rpms.
or do u think the gas station ripped me off and gave me less than 93oct?? because it was runing fine until i pumped gas in it then 20 min later this started to happen.

[mikel]

Does this car have a stock cam?

Thanks