ezzey

iTrader: (3)

title says it all.. i've done a TON of reading and searching, and i know that narrowband FORCES closed loop to run 14.7, but what about wideband? Does wideband allow closed to run leaner then 14.7? (stoich)

thats all

dj

BluEVOIX

iTrader: (69)

No you can not run leaner with a narrowband in closed loop. However some wideband controllers (not just o2 sensor but the whole kit) will allow you to splice into their circuit and some how send a false signal to the Ecu. Basically you tell the wideband that your set target a/f and it will send the correct voltage to the Ecu to read as the stoich target.

Other than that then you'll have to be in open loop with the factory narrow band there is no other way.

Why are you trying to do this? If you want to get better gas mileage on 93 octane, I think you would benefit more from tuning the timing table. Advancing it will help harvest more of the combustion for pushing the piston = more power per less throttle. If your on E85 , I'm just guessing maybe it might benefit more to cut the fuel because you do run 20-30 % more fuel.


Here is the how to for the wideband closed loop:
https://www.evolutionm.net/forums/ec...o2-system.html

ezzey

iTrader: (3)

Thanks for the reply. Yes im going after better fuel economy and was reading a few economy threads/tunes. Thanks for clearing up the narrowband/wideband kit that cheats the ecu into running any desired afr.

Im running on 93 and gonna play around with the timing sometime today. Currently set my afr's to 15:1 (bounces lightly around [open loop]) while cruising on the highway.

Thanks again, ill post how things go after my adjustments.

evo8426

iTrader: (27)

changing the number is not going to make the car run leaner unless you change open/closed loop to allow for it to run leaner

ezzey

iTrader: (3)

unless you change open/closed loop to allow? Currently running only in open loop, so making the changes isn't an issue. Just wanted someone to confirm whether or not it is possible to run leaner then 14.7 in closed loop; and that answer is yes with proper wideband kit.

BluEVOIX

iTrader: (69)

Honestly I did try messing with the open loop and adjusting a/f ratio to 15.2-15.5 area. I didnt really notice any difference, maybe 1 mpg at best that could have just been driving style behavior.

If I were you, I'd leave it closed loop and mess with the timing. Unless your E85 then leaning out might also help to, but timing is key in my opinion.

SLO-EVO

iTrader: (52)

I tried this a while back. I found that not boosting all the time and having a lighter foot yeilded better results than leaning out the closed loop.

ezzey

iTrader: (3)

To above posts:

I will play around with the timing most def. As far as leaning out and seeing results, i do notice the difference. Now as far as driving habits, i dont rape my gas pedal, and my 35r doesn't sppol quick at all so i drive with very minimal boost already.

And you're probably right, im not going to touch my closed loop 14.7 afr. I just wanted to know if it was able to be changed. Once i get my wideband hooked up to the ecu i can then finalize my setup and run open loop for warmup, closed loop for regular driving conditions and open loop for WOT.

thanks again for all the info, greatly appreciated.

dj