Let's start over......
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From: San Angelo, TX
1 octane point ain't going to make that big of deal.....but what size is the gas tank??? canned tunes are a bit more forgiving and conservative than custom tunes...imo
rule of thumb before switching up in octane in the tunes is change tunes on the 2nd tank of the tune you'd like to run....
rule of thumb before switching up in octane in the tunes is change tunes on the 2nd tank of the tune you'd like to run....
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From: DFW
Merry Christmas yall
I texted Coy about it, but basically the PCM will pull timing if necessary to keep engine running at optimal conditions for what ever octane is in the truck
I texted Coy about it, but basically the PCM will pull timing if necessary to keep engine running at optimal conditions for what ever octane is in the truck
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From: In the fast lane from LA to Tokyo...
I'd play it safe....change tunes on the second tank...imo
Technical Article Contributor
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From: In the fast lane from LA to Tokyo...
canned and custom tunes narrow the parameters for a given octane....you can go up with higher octane on a lower octane tune but not lower octane on a high octane tune...
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From: Houston and College Station, TX
I always run a few 5-10 gallons baby fill ups of 93 prior to switching the tune when I have a full tank of 93 in it. I run the 87 all the way down and then do the same with the baby fill ups.
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From: In a house, in a small town
All this discussion about octane ratings and tunes makes me like my diesel even more. The only thing I have to worry about is if I accidentally put Off Road diesel in it. 
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Jim
Jim
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Not at all. I have lots of reasons to like diesel motors over gas so it's just more of a confirmation than anything else. Heck I can run my truck on Jet-A if absolutely had to in a pinch.
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From: Sask. Canada
when you drive a dodge you have to keep a spare with you
that about sums it up lol
Last edited by Gotts2BMe; Dec 26, 2013 at 11:36 AM.