I have a 1715, an older "max tune" model. I loaded it and am quite happy with it. I had a tank full of 87 octane put in after I tuned it (about 2 tanks later) by accident. I drove it to work the next day (~40deg F ambient) and did not notice any negative effects (pinging etc) of course I was babying it the whole 8 miles. The truck does reach operating temps about halfway to work..so engine temp was at a normal level..I did notice the performance was not quite the same.
I slowly pushed it a bit during acceleration (onto hwy) but never WOT. Still nothing sounded or felt out of order. I finished the tank and switched back to high octane.
Question:
Did I do damage to the engine, even though I could not "hear" it?
Is it possible that the cooler air intake temps made it possible to avoid serious knocking?
I'd appreciate your thoughts on this one...If its possible, I'll run 87 through the cold winter and switch back to high octane when the weather breaks.

Many thanks,

 

I not familiar with the 1715 “max tune” model but if it’s supposed to be for premium fuel, 91-octane thru 93-octane, you best not run 87-octane for long even though you can’t hear it knocking. The knock sensors will retard the timing somewhat but it not a good idea to continue to use fuel not recommended for the tune IMO

This topic has been discussed in detail somewhere on this forum as to the whys’ but it’s been a while since I’ve seen it; a thorough search will probably turn up much info

 

Well, I really couldn't tell you if you damaged your engine, it's rather hard to see the combustion chambers from here.

However, if that is all that has happened, then it sounds to me like it's possible that you just may have gotten lucky, and the knock sensor protected you -

I'd make sure to remove any premium gas tuning until every bit of the 87 octane is worked out of it, and then fill it up with the best quality premium gasoline available before reloading the premium gas tuning.

Don't think that you are always supposed to be able to "hear" detonation - there are several forms of detonation, some of them completely inaudible! In fact, I have on occasion ridden inside someone's F-150, with them driving, and I could very clearly hear the engine pinging - yet they swore their engine *wasn't* detonating, because they couldn't hear anything. Of course, I've been tuning engines most of my life, and have been a hot-rodder for decades, so I will usually hear some things that those without that kind of experience may not - perfectly natural.

Hopefully you'll be OK, and will have simply made a mistake that has happened to a number of us once in a while!

 

Thanks Mike...will do.

 

You're very welcome, & good luck my friend!