Evan02

I recently got one of those DiabloSport InTune tuners from AM. I didn't realize that I forgot to set the octane rating on all the tunes, so when I got it they were all 87. So when I got the tuner, I ordered some new tunes with better octane ratings but in the mean time I loaded up the 87 performance tune.

I ended up hearing valve clatter when I was in 4th or 5th gear, I guess the timing was too advanced for the octane rating.I set it back to stock and I'm going to fill my tank up with some 91 when I get the new tunes loaded onto my tuner, so its not a big deal or anything.

But I was just curious, has this happened to anyone else?

school boy

more than likely have detonation. Too low of octane or bad gas with too much timing or load will cause it.