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Flex fuel tune

beefcake

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its not much, the e85r will ramp the timing in sooner, maybe .1 on an n/a car
 

TRPCANA

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How large is the diff between flex and a true e85 tune?

I switched to lunds flex tune after running PBD for awhile and i wasnt really happy with their setup. With lund i am 100% happy. Lunds flex give you the option to run literally any ratio of 93 or E85, no draining the tank, etc. The difference between the two, once fully on E85 btw isnt much. Both tunes have the same max timing a WOT and will feel the same at WOT, but the E85r tune is a bit more aggressive in midrange and partial throttle around town. Personally i daily'd the flex for awhile but then made the switch to E85r since i only use e85 now and i prefer the R tune. Some notes you should be aware of, nothing negative but just so you know upfront since seems your on the fence.

Lund flex tune--upon your first time loading it, id drive around a bit to let the tune "settle" then head to the pump. At this point i assume youve driven down to as close to E as you are comfortable with, while it isnt required, it does make the switch to full E85 faster and youll get the benefits faster. Otherwise youll have to burn through a few tanks to get to full E85. So youve driven down to lets say 15 miles to E or whatever. Fill up with E85 then sit at the pump and idle for a few min, your first start may seem rough but probably wont be due to 93 still in the lines. Let the car adjust, and watch two very important values on the Ngauge, ALC learned flag and Ethanol content %. ALC learned will be displaying a yellow zero and you are not safe to go to WOT until this displays a red "1" meaning it has locked the E content value into the tune and you safe to go bananas. This process is known as relearn and it can take up to 15 min or so the first time, and is triggered every time you fill up with more than 4 gallons of fuel. Now back to your first fill up, sit and let the car idle as you watch E content %. it will initially display 10% but then very slowly start to rise depending on how much 93 you left in the tank since that will be diluting the E85 you just put in. Lund advises to wait until 40% to start driving but personally that takes a long time and can cause people at the pump to start to get impatient, i waited till about 20 and then slowly drove out of the area and moved to the side until i hit 40%. Then i took the car out and started driving around town at a normal pace, nothing aggressive. Driving will mix the fuels faster and start to increase your percentage and help lock in the flag faster. If you are sitting at idle waiting for the 40%, small revs can help as well. My first fill up i got to a max of 50% before the flag locked in. I just kept burning gas then filling up till i got steady values of 75 to 80. Now fast forward to your fully swapped over, your E content is steady at whatever it topped out at and your driving around town, two things to remember, because of the way the flex tune works every time you start your car it will likely take a bit more time to start than normal, this is fine and nothing to be concerned with. And number two, the ALC relearn flag will reset every time you fill up which means no going to WOT until it locks in. Again, you can drive normally and semi aggressively but dont go full WOT until the flag locks. Overall a great tune to use and has good pull and power on e85, very useful if E85 isnt as available in your area.

E85r tune--Love this tune, do not switch to this until your E content averages 70 and above. Two great things this tune has that were minor inconveniences in the flex, 1, this tune starts the car right up no lag, and two, fill up and go. No flag relearn process. The logic in the tune already is built for E content so it doesnt need to relearn every time you fill up. The additional mid range and partial throttle is nice, especially when merging onto the freeway from on ramps, etc. Honestly if E85 is readily available to you id run the flex, make sure everything is good to go then switch to R and never look back. Lund will help you with the process every step of the way and will even setup your ngauge will a datalog file that automatically sets up the values it wants you to monitor which is convenient, other tuners have you manually select these values. All in all obviously im biased to Lund, ive never had a single issue with their tune and i did have several with PBD that never got corrected despite many revisions. Good luck.
 

Stymee

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Will the flex or the E85r tune pass emissions?

What kind of mpg r u getting on straight E85
 

Zelek

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Will the flex or the E85r tune pass emissions?

What kind of mpg r u getting on straight E85
E85r tune can pass emissions if it's done right, but don't count on it. They're tuning your car for performance, not to pass emissions. Most tuners will tell you that. I passed emissions on one of my other tunes because majority of my stuff was turned off instead of on. Not available (grayed out) options on emissions stuff allowed me to pass in Texas. It's probably not the same everywhere. Not Ready status would have failed me.

11-12 mpg on E85. Might get 13-14 if you baby it.
 

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Stymee

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E85r tune can pass emissions if it's done right, but don't count on it. They're tuning your car for performance, not to pass emissions. Most tuners will tell you that. I passed emissions on one of my other tunes because majority of my stuff was turned off instead of on. Not available (grayed out) options on emissions stuff allowed me to pass in Texas. It's probably not the same everywhere. Not Ready status would have failed me.

11-12 mpg on E85. Might get 13-14 if you baby it.
Wow that’s not too bad of a loss since E85 is cheaper

Did u pass on the Flex?

Thanks for the info
 

Zelek

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Wow that’s not too bad of a loss since E85 is cheaper

Did u pass on the Flex?

Thanks for the info
Flex Tune was the same way with the options grayed out. Both would pass.

Now my current tunes, all of the emissions stuff is back on and O2\HO2 are both red so that's a fail again. May have to get a JLT intake again just for emissions... lol.
 

Bluemustang

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Flex Tune was the same way with the options grayed out. Both would pass.

Now my current tunes, all of the emissions stuff is back on and O2\HO2 are both red so that's a fail again. May have to get a JLT intake again just for emissions... lol.
Did you sell it?
 

Zelek

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Did you sell it?
Ya, I did. Didn't realize that the new Lund tunes all come with the emissions stuff on because of the EPA fines that have been going around.
 

Bluemustang

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Ya, I did. Didn't realize that the new Lund tunes all come with the emissions stuff on because of the EPA fines that have been going around.
They won't revise it for you?
 

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Zelek

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They won't revise it for you?
They won't turn off the O2's any longer if you ask for it. They don't want to be responsible for the fines if someone tries to come after them. You have to do that yourself now.
 

Bluemustang

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F***. I guess I am screwed now then when I have to renew.
 

Bluemustang

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If true this is gonna hurt tuning companies, A LOT over time. If people find out they can never pass emissions, many will say forget it stay stock.

I guess question is how do we turn the O2s off ourselves? Is that a tuning option on devices? If so, the tuner can open up the options, then let the user do what they want and be responsible for it.
 

Stymee

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I’m confused, if they leave the 02’s on then why wouldn’t it pass? Are you saying earlier 2016-2018 tunes turned off criteria for emissions but now the companies that tune are more careful as to what they turn off?

Hell if I can’t pass emissions, then why tune the car?
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