I am one who had pinging issues with the Upsolute. But I am a worst case example. The summertime temps here in Phoenix are 110 F daily, and the street surface temp is easily 150 F. All of that heat rises and soaks into the engine compartment, and that coupled with the fact that we only have 91 octane here and the air conditioning is running 24/7 adding even more heat load and compressor load to the engine...all of this adds up to grueling conditions for an engine.

The pinging was quite noticeable in the middle of summer, but the car still returned good mileage - still better than without the chip. Didn't like the pinging, but could do nothing about it. It wouldn't ping in the morning, though, when the temps there would be in the 70's or so. I wish I could describe the pinging better for everyone, but it is a subjective thing. I have been in cars that pinged more than this, so it isn't nearly as bad as many I have heard. But it was definitely more than just barely noticeable. Any gear-head (like me) would immediately notice it but consider it in a non-alarming range. I guess you could argue that any pinging is bad, but again, I still saw increased mpg's so it was probably just fine...but I will add that a full 4,000 rpm launch from a dead-stop would bog the engine...the computer probably was pulling back the timing as much as it could to stop the ping which resulted in the bog. That bog condition was only there in the middle of the summer at worst case conditions, so again, most people won't even experience that.

I believe the Upsolute Chip is really tuned for 93 octane for these extreme conditions. It probably is ping free on 93, but can't guarantee it. If your daytime temps stay in the 90's, then 91 octane is just fine...it would just slightly ping in that temp range for me, and for me that would be just fine. Maybe not for some of you though...

By the way, I tried all the brands of gas here (Mobil, Shell, Chevron, Quiktrip, Shamrock) and didn't see a difference between them. Didn't try Arco because that is a known crappy brand and didn't want to confirm that.

Anyone else see Upsolute pinging issues in extreme temps?