wish i would have ran my denali stock..im heavier being awd 5700lbs with headers, no cats, intake and a tune from zippy and went 13.9s ..which was also zippys base tune for me.. i just sent the first set of logs to him and he made some adjustments and it feels faster now..and he says theres still plent more to go

 

My truck ran 14.4s bone stock on 20s.

Ran 13.4s with tune and cai on the same 20s.