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how much fuel?
Posted: Thu Nov 15, 2012 11:17 am
by sharkcohen
I'm running the 91 octane tune on my 2012 Challenger SRT8. As expected, I'm getting a small amount of knock, although it doesn't look like an alarming amount. So far, there is no LT knock. I'll be adding fuel and doing more data logging to see how it goes. Posting for info for others, and looking for advice on how much fuel should be added.

Re: how much fuel?
Posted: Thu Nov 15, 2012 12:00 pm
by mikel
maybe 5%

Re: how much fuel?
Posted: Thu Nov 15, 2012 12:56 pm
by sharkcohen
Thanks Mike, that might be about right. Here's a look at what 2% across the board did for me.

Re: how much fuel?
Posted: Thu Nov 15, 2012 1:35 pm
by mikel
your on the right path.
Re: how much fuel?
Posted: Fri Nov 16, 2012 1:04 am
by mopar-srt8
We have winter blend gas here with less heat energy than summer gas. The actual stoicometric mixture for winter gas is 14.2 when summer gas is 14.7 a/f meters are calibrated to 14.7. So if you are shooting for a AFR of 11.5 at WOT your meter will read 11.0. My car is a GWE 392 and I have fattened up the 91 octane tune +10 +10 +5 and at times I see the desired AFR at 10.8 and it feels like more torque. It is a good thing that I am running drag radials.
Re: how much fuel?
Posted: Fri Nov 16, 2012 11:51 am
by sharkcohen
Winter gas here, too (CA), thanks for the tip. I really need a wideband for the car.
Re: how much fuel?
Posted: Sun Nov 25, 2012 2:48 am
by sharkcohen
I finally ran a log of the stock tune to see how much if any knock I get on it. I think I need to reconsider where I fuel up.
