• Sign Up! To view all forums and unlock additional cool features

    Welcome to the #1 Dodge, Jeep and RAM Forum dedicated to FCA owners and enthusiasts. Register for an account, it's free and it's easy, so don't hesitate to join the SRT Forum today!


Another Flex Fuel thread.

1mean376

Law Enforcement
Member ID
#13680
Messages
8
Reactions
44
Likes
12
City
Holtsville
State
NY
Country
United States
Vehicle
1970 Challenger RT
#1
Sorry guys, I know there were a few but I haven't seen much input on what I was looking for specifically.

I am considering a flex tune on my build as the car is already set up with a magna fuel Pro Tuner 750 pump, bypass regulator, 10AN fuel line etc... I'm running just an ATI lower and stock upper.

I run a GM flex sensor on my LSA swapped car and I love it, I make about 90 more WHP on it than pump and the sensor/ECU allows for adjustment on the fly to whatever ethanol content gas I'm getting.


I know guys do flex tunes for hellcats using the 02 sensor readings to adjust for the ethanol content but how well does this actually work? Those of you running a tune like this, if you live in an area like I do where the ethanol % in "E85" is vastly different from station to station, have you seen any issues because of it this or does it seem to perform pretty well?
Also, who are normally regarded as the best tuners go to for a tune like this?

I already contacted OST dyno and they were one of the few tuners in the north east willing to tune my build since it's bit of a frankenstine build (6.2 into a 70 challenger) but they said they try to stay away from flex fuel tuning. Have to make a decision before I install these Demon injectors or return them and pick up some 1050x's or bigger for E85.

Thanks!
 


Jon-MooredPerformanceLLC

Active Member
Vendor
Member ID
#12838
Messages
284
Reactions
1,009
Likes
117
City
Martin
State
MI
Country
United States
Vehicle
2018 Dodge Challenger Hellcat
#2
I tune flex it is inferred from the widebands. Like you say you have a little bit of a different build than most. I would recommend bigger than the 1050s. FIC 1200, ID1300 or fic 1440s are all pretty good injectors for e85. There is a used set of 1300s for sale on the site.

Just like factory flex fuel cars it is not recommended to just floor it after filling up. There is a learning period for the inferred alcohol percentage.
 


Speedy!

Infomercial Producer
Staff Team
Founding Member
U.S. Marine Veteran
9 Second Best E/T
HFCOTM & HFCOTY
Member ID
#1070
Messages
6,317
Reactions
16,212
Likes
402
City
Interwebs
State
TN
Country
United States
Vehicle
Demon 170
#3
You'll have a unique setup, but flex fuel does work. Mike from OST helped me learn how to tune mine and it's been accurate and trouble free for a couple years. I was surprised to learn that GM is the only manufacturer that actually uses a sensor, the others just use inferred from O2 logic. I thought a sensor would be better, but who knows. Mine works so <shrug>.

There are some factory calibration files that it won't work with for some reason. If you happen to be unlucky and your PCM has one of those you can have it flashed to a known good calibration file. I'd check up on that for sure.

There are some rules of engagement as they were for flex fuel though, that I had to learn a long the way and could have saved time just reading a factory flex fuel vehicle manual LOL.

1. Don't try to swap back and forth between gasoline and E85 3-4 gallons at a time. The car will eventually figure it out, but it works a lot better if you fill up with one or the other from almost empty.

2. As mentioned above, give time for the calculation from one to the other to occur before going nuts on the throttle. Mine usually figures things out about 80% of the way in less than 5 minutes. That last 20% might take 15 mins or so.
 


OP
1

1mean376

Law Enforcement
Member ID
#13680
Messages
8
Reactions
44
Likes
12
City
Holtsville
State
NY
Country
United States
Vehicle
1970 Challenger RT
Thread Starter #4
Thank you both! For the injectors, the 1200's seem like a good idea. I run 1050x's in my LSA car on E and they are getting pretty close to maxed out at 700whp which I think the 6.2 should be making a little more than with just the lower. Even if they work, it won't leave me much wiggle room I guess if I ever want to do an upper.


I think I will talk to OST again when the time gets closer to tune. The owner seemed really knowledgeable so I really wanted to go with them for tuning (that and they were the only tuner I spoke to in the NE willing to tune by build) but he was pretty strongly trying to talk me out of E85 and said he wasn't a fan of using it on these cars.
Didn't quite understand that since I've seen such great results with it on my GM so I just figured the inferred logic tech didn't work as well as an actual flex sensor, but that doesn't seem to be the case from what you guys are saying and I can't see how there wouldn't be pretty significant gains on E even with only the 3 psi the 10% lower adds.


What I have found that I liked about E on PD blown cars too is even when the gains aren't huge, you can stay more aggressive in the tune with climbing IATS so things can be pushed a little further/harder before you have to begin pulling timing.
 


Jon-MooredPerformanceLLC

Active Member
Vendor
Member ID
#12838
Messages
284
Reactions
1,009
Likes
117
City
Martin
State
MI
Country
United States
Vehicle
2018 Dodge Challenger Hellcat
#5
Surprised OST would have not recommend e85 to you. @Speedy! knows him much better than I do but I have spoke with him at the track before. He has done a lot of e85.
E85 on this platform is a great fuel. I tune more e85 than race fuel.
Maybe he was trying to say since you were a lower only you could be tuned on pump fuel without issue.
I will say I don't know if OST tunes for FIC injectors. Some tuners don't like tuning them. I have never had an issue and run them in my personal cars. If you choose OST check with him on injector before purchasing.
 


Speedy!

Infomercial Producer
Staff Team
Founding Member
U.S. Marine Veteran
9 Second Best E/T
HFCOTM & HFCOTY
Member ID
#1070
Messages
6,317
Reactions
16,212
Likes
402
City
Interwebs
State
TN
Country
United States
Vehicle
Demon 170
#6
Mike at OST will try to talk you out of spending un-necessary money so maybe it was like Jon says above and you're setup would meet your needs on pump gasoline. You'll be around 14-15psi of boost with the stock upper and 10% lower which is Redeye supercharger OEM territory.

If you're already going to have fuel pumps, injectors, and the rest of a fuel system that can deal with E85 I'd get both tunes if it were me just so you have them. I've been using E85 in mine for a couple years and the car really does love it, especially at the track. I just run a tank or so of 93 through it once a month for peace of mind on keeping things clean fuel system wise so that's about the only time I use my flex fuel tune anymore.
 


vortecd

Poster Club Hall of Fame
Premium Account
Donating Member
9 Second Best E/T
HFCOTM
Member ID
#1248
Messages
51,125
Reactions
166,764
Likes
402
City
Middleville
State
MI
Country
United States
Vehicle
2016 Charger Hellcat
#7
If you have e85 in your area it is a no brainer. You have race fuel all the time in the car and even stock Hellcats can pull timing on 93

Jon did the tuning on mine and we picked about 75hp just on e85 and another 150hp with a pulley.
 


ostmike

Active Member
Vendor
7 Second Best E/T
Member ID
#1481
Messages
133
Reactions
339
Likes
67
City
Portersville
State
PA
Country
United States
Vehicle
2015 Hellcat
#8
Surprised OST would have not recommend e85 to you. @Speedy! knows him much better than I do but I have spoke with him at the track before. He has done a lot of e85.
E85 on this platform is a great fuel. I tune more e85 than race fuel.
Maybe he was trying to say since you were a lower only you could be tuned on pump fuel without issue.
I will say I don't know if OST tunes for FIC injectors. Some tuners don't like tuning them. I have never had an issue and run them in my personal cars. If you choose OST check with him on injector before purchasing.
Jon, you are correct. We have and continue to do ethanol tuning. For customers that drive their cars hard all of the time or race regularly this is a great option. For folks that drive to car shows and Sunday cruises the cost of upgrading may not be the best choice. With that being said we do try to provide customers with all of the information, including costs, fuel consumption, shortfalls of "inference based" logic and additional maintenance involved in the process of running ethanol (more frequent oil changes, fuel storage requirements etc.). As Speedy mentioned, if a customer has a build that will not benefit substantially by running ethanol we try to advise them accordingly. This is based on over a decade of running ethanol on this platform and many customers converting to ethanol and eventually converting back due to the cost of the fuel and maintenance. If pump E85 was substantially less expensive in our area then it would be a different story. However it is not and the cost of the additional fuel consumption can be prohibitive for a true daily driver. The Flex OS patch certainly makes this option more user friendly for 2015 and newer 6.2 based cars. With this option there is still the added expense of injectors, fuel pumps etc. to consider in the decision making process and for many customers it is worth the expense. We just want our customers to have all of the information. Now for the sales pitch - At OST Dyno we do stock drums of Renegade Pro E98 and Pro E85 for those interested in running ethanol. We also stock most sizes of ID injectors, our dual fuel pump system and offer Flex Fuel tuning :)
 


MiHiHemi

500 Posts Club
Founding Member
Member ID
#1016
Messages
812
Reactions
2,446
Likes
132
City
Parker
State
CO
Country
United States
Vehicle
2015 Challenger SRT 426
#9
Jon, you are correct. We have and continue to do ethanol tuning. For customers that drive their cars hard all of the time or race regularly this is a great option. For folks that drive to car shows and Sunday cruises the cost of upgrading may not be the best choice. With that being said we do try to provide customers with all of the information, including costs, fuel consumption, shortfalls of "inference based" logic and additional maintenance involved in the process of running ethanol (more frequent oil changes, fuel storage requirements etc.). As Speedy mentioned, if a customer has a build that will not benefit substantially by running ethanol we try to advise them accordingly. This is based on over a decade of running ethanol on this platform and many customers converting to ethanol and eventually converting back due to the cost of the fuel and maintenance. If pump E85 was substantially less expensive in our area then it would be a different story. However it is not and the cost of the additional fuel consumption can be prohibitive for a true daily driver. The Flex OS patch certainly makes this option more user friendly for 2015 and newer 6.2 based cars. With this option there is still the added expense of injectors, fuel pumps etc. to consider in the decision making process and for many customers it is worth the expense. We just want our customers to have all of the information. Now for the sales pitch - At OST Dyno we do stock drums of Renegade Pro E98 and Pro E85 for those interested in running ethanol. We also stock most sizes of ID injectors, our dual fuel pump system and offer Flex Fuel tuning :)
Been talking with my engine builder about converting and maybe using one of those Flexfuel kits like GM has. He said they don’t work on Dodge because he can’t alter the ignition curves making it useless. Have you guys run across anything that allows proper tuning on “E” without having to pull out the laptop? I have an N/A 426 stroker (closer to 440) with 12.5:1 compression.
 


ostmike

Active Member
Vendor
7 Second Best E/T
Member ID
#1481
Messages
133
Reactions
339
Likes
67
City
Portersville
State
PA
Country
United States
Vehicle
2015 Hellcat
#10
Been talking with my engine builder about converting and maybe using one of those Flexfuel kits like GM has. He said they don’t work on Dodge because he can’t alter the ignition curves making it useless. Have you guys run across anything that allows proper tuning on “E” without having to pull out the laptop? I have an N/A 426 stroker (closer to 440) with 12.5:1 compression.
Here's a common question we get. For the GM's we are able to install a true ethanol content sensor and a signal directly into the GM PCM. This is true flex fuel tuning and is not "inferred".
If you were to contact us for tuning, did not want to "pull out a laptop" and this was not a 6.2 based PCM we would recommend either a straight ethanol tune or a straight race fuel tune. If this was a 6.2 based PCM then the choices would be the same with the additional option of a inferred Flex fuel tune. If choosing the Flex option I would not recommend driving the car to the track on 93, draining the tank, adding ethanol and then pulling into the staging lanes. You would need to drive it to let the ethanol content be learned/inferred.
 


GNBRETT

1000 Posts Club
Member ID
#9039
Messages
1,040
Reactions
1,423
Likes
162
City
Kingsport
State
TN
Country
United States
Vehicle
Trackhawk, RS3 Swapped Golf R, Turbo Stang, Golf R
#11
Personally, the only way I would do a flex tune is to have the option to run 93 octane at cruising speeds. I would never smash it unless it was on E85 but two each his own.

Very few tuners offer flex tunes. The two top that come to mind are Dusterhoff and Z and neither offer flex tunes. IMO, its just for driving long distances that u dont want to make on E85 but like Speedy says the time it takes to compensate is not all that fast sometimes. That doesnt give me a warm and fuzzy feeling......

Ford and Chevy have much faster processors than Dodge does and its REAL flex fuel. But Satera seems to offer them but u dont see ANY shops posting big numbers on 93 octance while flex tuned its always the E85 where they lean on it.

Would be great if it worked flawlessly but with a $20k short block thats not something I feel comfortable doing but I will admit the idea is really inviting. If it was so reliable ALL tuners would offer it.
 


Speedy!

Infomercial Producer
Staff Team
Founding Member
U.S. Marine Veteran
9 Second Best E/T
HFCOTM & HFCOTY
Member ID
#1070
Messages
6,317
Reactions
16,212
Likes
402
City
Interwebs
State
TN
Country
United States
Vehicle
Demon 170
#12
You must have misunderstood me. Mine calculates to 80% accuracy in about 3 minutes (maybe 5 depending on stop lights). The other 20% happens in about 15 minutes.
 


drive_55_not

U.S. Navy Veteran
Member ID
#3814
Messages
15
Reactions
21
Likes
2
City
Lincolnton
State
NC
Country
United States
Vehicle
2020 Hellrasin Challenger HellCat
#13
I have a flex fuel tune from Jon and it picks up the inferred corn % pretty quick, Well Less than 15 minutes to get the correct ethanol read

Power on 93 is going to depend on how much timing you dial in, My 93 tune from a local tuner only has 10degrees WOT, dyno'd 780/700

I ran essentially identical times with Jon's flex tune as I did with a local tuners MS109 tune which had more timing.

10.15x @136 on MS109 mid-80's air temp, 10,22 @136 on E80 and in low 90's, I had a tad of tire spin on the 1-2 upshift on that pass also.

That MS109 tune dyno'd 835/800. More low end timing makes a lot of low end torque...


And the good thing with flex fuel, I drove 120miles to the track and raced on E80, Filled up with 93 and drove home.



.
 


Jon-MooredPerformanceLLC

Active Member
Vendor
Member ID
#12838
Messages
284
Reactions
1,009
Likes
117
City
Martin
State
MI
Country
United States
Vehicle
2018 Dodge Challenger Hellcat
#14
I have a flex fuel tune from Jon and it picks up the inferred corn % pretty quick, Well Less than 15 minutes to get the correct ethanol read

Power on 93 is going to depend on how much timing you dial in, My 93 tune from a local tuner only has 10degrees WOT, dyno'd 780/700

I ran essentially identical times with Jon's flex tune as I did with a local tuners MS109 tune which had more timing.

10.15x @136 on MS109 mid-80's air temp, 10,22 @136 on E80 and in low 90's, I had a tad of tire spin on the 1-2 upshift on that pass also.

That MS109 tune dyno'd 835/800. More low end timing makes a lot of low end torque...


And the good thing with flex fuel, I drove 120miles to the track and raced on E80, Filled up with 93 and drove home.



.
Flex is for sure nice for the fill up and drive both ways and no tune change. The tune is a little more conservative than a race e85 tune for saftey purposes. If you decided you want a race tune where you know what the percentage of fuel is feel free to reach back out.
But it sounds like you are happy with the tune. I’m glad to hear that!
 


drive_55_not

U.S. Navy Veteran
Member ID
#3814
Messages
15
Reactions
21
Likes
2
City
Lincolnton
State
NC
Country
United States
Vehicle
2020 Hellrasin Challenger HellCat
#15
Flex is for sure nice for the fill up and drive both ways and no tune change. The tune is a little more conservative than a race e85 tune for saftey purposes. If you decided you want a race tune where you know what the percentage of fuel is feel free to reach back out.
But it sounds like you are happy with the tune. I’m glad to hear that!
Hello Jon,

It looked like we were pulling 3 degrees on those pass from high charge temps, IAT's were 160 in 2nd and 175 at the stripe.


The Sheetz pump was E81 last week when I tested it. The bad thing about DD'ing E80, 14.5 mpg, 19 on 93.

It may be too late in the year for me to run E85, I ran into that issue of these 274 pumps and 1050 injector being too small for cooler temps you warned me about.

It was 58degrees last night when I left werk so I decided to do a run down across the Mexican border and log it.

FP dropped to 72 and IDC went to 87 at the top of 4th and 5th. Log showed it added 2.5 degrees timing.

So No E80 for me in these <60 degree days. Sad face..

But it felt like a rocket going down there.

I really need to install rear control arms before I add more power, The stock suspension parts are tearing up my DR's.

And then my next power mod will be a little cooling shot of nitrous for next year.

OK, likely it'll be a moderate shot.

But no bigger than 200. :)



./
 


GNBRETT

1000 Posts Club
Member ID
#9039
Messages
1,040
Reactions
1,423
Likes
162
City
Kingsport
State
TN
Country
United States
Vehicle
Trackhawk, RS3 Swapped Golf R, Turbo Stang, Golf R
#16
Thats a LONG freaking time......

You must have misunderstood me. Mine calculates to 80% accuracy in about 3 minutes (maybe 5 depending on stop lights). The other 20% happens in about 15 minutes.
 


fubar569

1000 Posts Club
Founding Member
9 Second Best E/T
Member ID
#1073
Messages
1,186
Reactions
1,669
Likes
162
City
Bradford
State
PA
Country
United States
Vehicle
2018 Charger Hellcat
#17
It's not THAT long. The coarse learn happens within a mile or 2 and the fine learn does take a bit but you're well within margin of error by the time you are a few blocks away from the station. Also if trims vary more than a certain amount it will repeat this process to compute content again.

I Don't think I've ever been off more than 10-15% unless there was a legitimate physical issue or i got stuck in a really odd cell at cruise.

I've been on Curt's flex tuning with pullies as small as 2.79 since late 2019 with a dedicated "kill" tune for the 2.50 pulley on 80+ percent ethanol and both are pretty decent now. Makes good power and I've probably got more miles on the 2.50 setup than anything. I even tow with it in that configuration. Logs all look good.

The only reason I am contemplating switching is the blower needs to come off due to noise (shocker right?) and I'm not sure if it's time to go big or go home yet...but I have ZERO complaints about this setup or Curt's tuning of it. It's been an almost perfect daily.
 


Speedy!

Infomercial Producer
Staff Team
Founding Member
U.S. Marine Veteran
9 Second Best E/T
HFCOTM & HFCOTY
Member ID
#1070
Messages
6,317
Reactions
16,212
Likes
402
City
Interwebs
State
TN
Country
United States
Vehicle
Demon 170
#18
Exactly, that's just how it works (same as factory FF Dodge btw) and that's going from 93 to full E85 as well. You gotta also remember it takes a few minutes for the new fuel to get through the lines and fuel rails. I actually set mine to delay calc by 2 minutes (from memory) for that reason.

So I have 93 in the tank and it's on E. I put in 10 gallons or whatever of E85 and leave the station. In about 3 minutes it'll already be at E75 or E80 on the calc but continues to fine tune for about another 15 minutes before it "locks" and gets to E85. Sometimes it's faster if I don't get caught by red lights and can cruise but my typical route with stop and go....15 minutes which doesn't seem "freaking LONG" to me.

If you stay with the same fuel most of the time, it's immediate since it's not having to figure much out. I've gotten to where I run my standard E85 tune most of the time these days and only put in the flex tune once a month or so to run a tank of 93 through the car.
 


Last edited:

GNBRETT

1000 Posts Club
Member ID
#9039
Messages
1,040
Reactions
1,423
Likes
162
City
Kingsport
State
TN
Country
United States
Vehicle
Trackhawk, RS3 Swapped Golf R, Turbo Stang, Golf R
#19
Is it common for guys to run stright E85 down there all the time in TN? I mean, is it that available? Its a novelty where I come from thats why im asking. Seems too good to be true. Especially for Turbo guys.

Exactly, that's just how it works (same as factory FF Dodge btw) and that's going from 93 to full E85 as well. You gotta also remember it takes a few minutes for the new fuel to get through the lines and fuel rails. I actually set mine to delay calc by 2 minutes (from memory) for that reason.

So I have 93 in the tank and it's on E. I put in 10 gallons or whatever of E85 and leave the station. In about 3 minutes it'll already be at E75 or E80 on the calc but continues to fine tune for about another 15 minutes before it "locks" and gets to E85. Sometimes it's faster if I don't get caught by red lights and can cruise but my typical route with stop and go....15 minutes which doesn't seem "freaking LONG" to me.

If you stay with the same fuel most of the time, it's immediate since it's not having to figure much out. I've gotten to where I run my standard E85 tune most of the time these days and only put in the flex tune once a month or so to run a tank of 93 through the car.
 


jonx96

4000 Posts Club
8 Second Best E/T
HFCOTM
Member ID
#4957
Messages
4,275
Reactions
10,628
Likes
302
City
Small town
State
MI
Country
United States
Vehicle
2019 Challenger Redeye
#20
Is it common for guys to run stright E85 down there all the time in TN? I mean, is it that available? Its a novelty where I come from thats why im asking. Seems too good to be true. Especially for Turbo guys.
I have 3 stations in a 15 minute drive by me in Michigan. Raise that to a half hour and there’s 8 or 9 if I were to guess.
 




Top