I have some questions about octane and it's relationship to custom tunes on the xcal2. I just asked this of Troyer in an email but I am curious as to what people's experiences are.

First, can the octane level for the tune be adjusted by the user (me) on the xcal2 before it is uploaded? I saw a mention of this in another thread.

Second, just how touchy is the octane level for the tunes? If I had a 93 high perf tune and was travelling and only found 91 on the road, would that cause any real problems other than a non optimal tune? If so, should I have the tunes done for 91 and if I can get 93, so much the better? I am seriously lacking info in this deptartment.

Any help you can offer would be great, since I need to nail down the tunes I want with Troyer.

 

Hi jmcmike,

First - yes, if you had us tune it for 93 octane, but ended up somewhere where you could only get 91 octane and actually had a problem with detonation, you can remove spark advance from your tuning, no problem.

Second - our custom tuning is indeed set up for each specific level of octane. However, the knock sensor system has a significant amount of range in the 2004 & newer F-150's (not as much in the 2003 & earlier trucks), as much as 12 degrees of retard capability - and that's a huge amount, so it's rare for anyone tuned for 93 to actually get audible detonation for 91 octane, even in a 1999-2003 F-150 - it has to be pretty darned bad fuel to make that happen.

Of course generally speaking, you'll want to run the tuning for each level of octane, that is how the truck runs best. But if you find yourself in a scenario where you need to reduce spark advance, you can do it that way - or simply dial down to a lower octane tune, which is the easiest way to do this, and that is what we recommend, rather than reducing spark manually - but it can be done either way, and when you do it manually, you can reduce spark in specific rpm ranges.

If you'd like to get more advice on which tunes to pick, please feel free to give me a call personally - if I'm not available at the time you call, I will return your call and go over all of this with you, OK?

Thanks, & good luck!

 

Thanks Mike. So is "removing spark advance" the same function in the xcal2 as "dialing down to a lower octane" or are they discrete functions?

 

Ok so I've got a question that this thread started. As previously stated I ordered the 87P, 87T, 93P tunes. Assuming (which is likely) that I fall in love with the 93P and I have to tow, could I run an 87T on 93 or should I take the truck back to stock?

I know that one should always run the matching octane but in the above situation what is the best solution?