I just recently tuned my GSR, and noticed a drastic decrease in gas mileage (from 32miles/gal ---> 22miles/gal). A/F ratio averaged about 13.6 @ WOT. My current NARROW THROTTLE Settings are set at -2 from 1000-9000RPM.

I'm running a SKUNK2 P28, with the FPR set at 40psi.


My question....

To gain better gas mileage (city/hwy miles), could I lean out my Narrow Throttle fuel settings?
If so, what would be a safe range?
Between what RPM range should I lean out more?


TIA

 

It really depends on the fuel and timing maps you have stored in the ECU. I'm assuming since you're using a SKUNK2 program, the fuel/timing settings are anything but gas mileage friendly. On average, by decreasing the correction from 0%, it will lean out the fuel and also advance timing (again, depending on the timing maps). Personally, I wouldn't use any aftermarket chip in my ECU. I like to see what's actually going on in there.... BTW, do you know if the SKUNK2 program eliminates closed-loop mode? If so, then that's your problem.

As far as the V-AFC settings goes. I would lean out the partial throttle settings within the RPMs you keep the engine in during most of your daily driving, say 1k-4k rpms. Just do an even decrease in correction until your gas mileage is satisfactory... I can garantee you that you will not get as good mileage as the stock P28 program though.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by MrTodd &raquo;</TD></TR><TR><TD CLASS="quote">It really depends on the fuel and timing maps you have stored in the ECU. I'm assuming since you're using a SKUNK2 program, the fuel/timing settings are anything but gas mileage friendly. On average, by decreasing the correction from 0%, it will lean out the fuel and also advance timing (again, depending on the timing maps). Personally, I wouldn't use any aftermarket chip in my ECU. I like to see what's actually going on in there.... BTW, do you know if the SKUNK2 program eliminates closed-loop mode? If so, then that's your problem.

As far as the V-AFC settings goes. I would lean out the partial throttle settings within the RPMs you keep the engine in during most of your daily driving, say 1k-4k rpms. Just do an even decrease in correction until your gas mileage is satisfactory... I can garantee you that you will not get as good mileage as the stock P28 program though.</TD></TR></TABLE>


I'm not sure if closed-loop mode is eliminated. I will call Skunk2 today, and find out. I bought a full tank of gas today, and leaned out my narrow throttle from 1.5k-3.5k to -3....I will see if that improves my mileage.

Thanks for the input!