Going to pick up the truck tonight Man, I've really missed that thing.

 

Detonation can make for a bad day. =) So you think it was definately the chip? Were there any other factors out of the ordinary? Air temp, humidity, etc.? What about gas?

 

Chip yes. Although the other three factors do make some change, should not be enough to cause the reaction I had. If that was the case there would be alot more guys going through what I did. I'm currently looking for a way to find out what program was actually on that chip.

 

Drop-Top, I'm assuming that the chip programer isn't accepting any responsibility.

 

drop top,

I've wondered what would happen to those who made changes in the summer when cooler air hits. With cooler temperatures I would think they might see minor deto but not to the extend of your's.

Something to think about...

John

 

Yes I agree, if you are tuned on the edge....lookout. If your a/f is from a tailpipe probe and its close, say 12.2 or so, you might be pushing it on a nice cool dry day.

Outnumbered, of course not, but I have not formally told him I think it is. We are going to tear the motor down and try to get the chip read first befrore formal proceedings. Thanks to the net he probably has caught wind of the deal.

 

so what exactly should your a/f be? What are the "safe" zones to be in. I live in Chicago and the winters can get mighty cold.

 

Safe, 11-11.5 per Johnny at JLP assuming other parameters such as timing are correct. From what I learned with my blown cobra and my harley, maximum of 13 with a blower and that is with spot on tuning and a 4 leaf clover in your pocket. Of course a/f is not the whole story, timing, boost ect ect. Much to much for this feable mind, I'll stick to medicine.

 

drop-top how long were you running the chip before this happened? also did you get any detonation before, or any warning signs. Or did it happen all of a sudden?

 

2-3 days, but never got on it hard until that fateful morning. I did not hear any detonation (there might have been) but it happened right when it went into O/D.....the point of most load on the motor.

 

All of the tuners will tell you that a tailpipe probe is not the most accurate way to get A/F numbers. I have discussed this with JDM and JLP and each said the best way was by removing the O2 sensor and inserting the probe. By doing this, you get a reading of .5 to 1 full point richer than by going in the tailpipe. (I have done all of mine through the tailpipe)

I discussed this with JDM at the FFW in Bristol, because I was concerned with my chips' 12.8 ratio. He said that there was no way that a J39 program (most conservative) had that type of ratio. He said it was probably anywhere between 11.5 and 11.8, and that my high number was more than likely a result of the method.

My JLP chip on the other hand has a reading of 11.8, so taking the aforementioned into consideration, it probably has a high 10 ratio.