Diablosport Forums

Ok guys I have researched the U7194 for a long time before I purchased it, I was debating custom tune or predator..I went with the predator and have had it for about three weeks now. When I first got the diablo I downloaded new upgrade and installed the Diablo tune with 93 octane, After driving really was not impressed other than the fact getting rid of DOD! Didn't really see an improvement over stock. So last week I decided that im not paying 3.90 gallon for 93 to drive back and forth to work so installed 87 tune and 87 gas.. after driving around little bit, big change, truck seemed to have more power shifted great and motor even sounded little better. So my question why is truck running better with 87 tune over Diablo tune. BTW I logged slop and adjusted PE on both tunes and slop was set at 0 with 87 tune and -8 on diablo tune. Any info would be great.

Just incase your wondering we are dealing with a 2008 Gmc Sierra 5.3 with Flex fuel, K&N drop in and Flowmaster 40 muffler replaced stock muffler.

Bump.

I found basically the same thing with mine! Its an 01 2500HD 6.0L. I have modded the 87 tune to my liking and just got back from a trip towing the trailer and bikes camping etc. I gained some ponies but I also gained 3mpg while towing!! Compared to the same trip untuned. You dont need to run 93 with the trucks and you can tune 87 to run quite well!!. Just my thoughts. Similiar mods buy the way!