Afr at full throttle

[white1]

What in the world is that symbol?

My Hellcat is a 2016 and stoich works properly for the fuel being burned, so E85 shows 9.5-9.8 at idle on the dash gauge. Looking at a 2019 RE factory tune file it has all the same stoich tables so I "assume" it would work the same. It's probably easier for a tuner to just change injector data for E85 since you're just changing one thing. To make the dash read actual AFR requires about 12 changes if memory serves. I personally prefer it though to keep track of what fuel I'm running.

When I applied the flex patch It seemed to read actual AFR but I had some issues with my alcohol composition that I didnt trust, so I just did a straight E70 tune. I wonder if that might be one reason my AFR reads the way it does.

 

[jonx96]

When I applied the flex patch It seemed to read actual AFR but I had some issues with my alcohol composition that I didnt trust, so I just did a straight E70 tune. I wonder if that might be one reason my AFR reads the way it does.

I just assumed if you do a "write entire" with a tune without the flex patch added it would take away the previous flex mod. But I could be wrong.

 

[Speedy!]

I think E70 shows an idle AFR on my dash gauge of like 10.0 - 10.5 from memory.

When I was dialing in my FF tune and wanted to test the calculation, I had to reload the 93 tune (which takes out all the FF code) then re-write the FF tune, and clear all adaptives. That would kick off a new calc when I fired the car back up, although on full E85 it would stumble a bit at first until if figured out what was going on and the trims went real positive. Took a couple starts and about 10 seconds of idling.

 

[white1]

I just assumed if you do a "write entire" with a tune without the flex patch added it would take away the previous flex mod. But I could be wrong.

I wasnt clear. I wasnt comfortable with the inferred flex as on regular gasoline I would sometimes show 9.3% but sometimes on the same tank of fuel it would show 37%
I loaded an older tune without the patch and just built a dedicated e70 tune

 

[white1]

I think E70 shows an idle AFR on my dash gauge of like 10.0 - 10.5 from memory.

When I was dialing in my FF tune and wanted to test the calculation, I had to reload the 93 tune (which takes out all the FF code) then re-write the FF tune, and clear all adaptives. That would kick off a new calc when I fired the car back up, although on full E85 it would stumble a bit at first until if figured out what was going on and the trims went real positive. Took a couple starts and about 10 seconds of idling.

I have a station about 1/4 mile from the house that consistently test 67-73% and one about 2 miles from the shop that test similar so Im fine not running the flex tune.

A friend of mine bought a Hellcat tuned by one of the big name tuners with a flex tune, and during TX2K this past year had some issues that seem to be from the flex side of things. Im pretty sure it was due to poor data supplied by the previous owner to the tuner, but my friend didnt want to risk it so we did a straight e tune on his as well and the issues cleared up. No matter how good the flex tune is, he personally will never trust it. I on the otherhand would like the advantages, but its not all that important to me

 

[DemonSRT]

I'd be salty too with all that work done to your car and running 9.70 at 141, I get it now LOL

Have a good day

Your right, I'd be very salty if that was the best my car could do with all of the mods he has. lol

Maybe he should start his own forum where he could argue with himself or with some of the others like him anyway.

Name calling is not the way or needed to state your opinion or disagree with someone.

Then maybe this forum might actually improve it's interest with a few of us that are starting to get bored with it and are not willing to give feedback on what we have found out and done on our cars.

 

[Speedy!]

When I was dialing mine in I'd have situations where sometimes the calc would be off. That was very frustrating as it would sometimes depend on how long I idled after filling up etc. Took some fiddling as there are multipliers that impact tables and the calculation so it is complicated.

I always recommend to folks to test going from pump gasoline to E85 in stages (I used 5-7 gallon increments) and then back down again from E85 to pump gasoline using the same method. Takes time, patience, and a lot of driving and most people won't go through it and just assume it's "OK" as they don't have the time and or patience but I wanted mine to be right so I took the time.

For racing I'll be using a dedicated tune for whatever fuel I'm using, whether that be Renegade RM109 race gasoline or Renegade Pro E85 ethanol.

 

[white1]

When I was dialing mine in I'd have situations where sometimes the calc would be off. That was very frustrating as it would sometimes depend on how long I idled after filling up etc. Took some fiddling as there are multipliers that impact tables and the calculation so it is complicated.

I always recommend to folks to test going from pump gasoline to E85 in stages (I used 5-7 gallon increments) and then back down again from E85 to pump gasoline using the same method. Takes time, patience, and a lot of driving and most people won't go through it and just assume it's "OK" as they don't have the time and or patience but I wanted mine to be right so I took the time.

For racing I'll be using a dedicated tune for whatever fuel I'm using, whether that be Renegade RM109 race gasoline or Renegade Pro E85 ethanol.

I got discouraged when my pump gas alcohol content would vary from 9.5-37 with no changes except driving down the road. Sometimes it would change sometimes it wouldnt. Just made me always question if it was going to be correct or not

 

[Speedy!]

Yeah that's too much of a swing. +/- 10 or so % I'll accept, but shoot for +/- 5% on mine.

 

[white1]

Yeah that's too much of a swing. +/- 10 or so % I'll accept, but shoot for +/- 5% on mine.

that was my thoughts as well

 

[YMMV]

I own a 16 kitty with a 2.85, pulley 775 injectors, 180 t-stat k% n cold air, blowrr spacers and thremo blanket. Tuned on 93.

Question is what AFR should I be running at full throttle? My gauge shows 10.5

So aside from all the other things going on in this thread (some good info in here as well) lol, I run a similar set up to you. I run 93 only and tuned by Barth. My AFR's run around 11.5-11.8.