Diablosport Forums

Using Mobil 93 gas. Too much knock with 93 tune so using 91 tune. Why does the stock and mpg booster pull harder than the 91 on the the low end especially? Are the 91 and 93 tuned to have more gains in the upper powerband? I logged the 91 with almost no knock, just an occasional blip when flooring it. Wondering if other 5.7 owners notice this...

you must be getting some knock, the MPG booster tune is a dog

If the perf tunes do not feel better, try different/better fuel or add some fuel to the tune at WOT.

Thanks

What kind of numbers were you seeing when looking at the knock in the logs? Mine's hitting up to 14 on the st and 3.5 on the lt when I mat the throttle. Even does that on the 87 tune..........

NealXB2003 wrote:What kind of numbers were you seeing when looking at the knock in the logs? Mine's hitting up to 14 on the st and 3.5 on the lt when I mat the throttle. Even does that on the 87 tune..........

I was nowhere near those numbers. It has been a month or two since data logging but I saw ST up to 3 occasionally with the 91 tune and more with the 93. The knock with the 91 tune was under WOT only but the 93 was knocking even under regular driving so i do not use that one. I definitely notice that my low end pull is definitley down with both performance tunes and that while regular driving so adding fuel at WOT only might solve part of the problem. I'm going to run my tank until it is almost dry because most of the time i fill up with about 16 gallons of 93 and 3 gallons of 89 (i normally use 89 for the stock tune or mpg booster only). I wonder if that is what's causing it...

question about your data logging. Are you logging in 45mins or only 9 minute increments? I am only data logging in 9 minutes increments and it is annoying when you do a run and then the log is full. Then you can only have that one log on file on the tunner while you driving so you can view several logs over time. What am I doing wrong not to get the 45 min log? I have the U7137 for the hemi ram.

Thats too long to log anyway. I never log more then 3-4 minutes at a time. Usually even less then that. The longer the log the longer it takes to go through, and its the same thing over and over again. Its just not necessary.

Yes i do agree it is to long to run for one run, but since they have the ability to fast forward through it all it helps. And I have to drive a few minutes just to get a run anyway so I start it when I leave the yard and watch it all.