will I benefit from e85/flex?

[ManBearPig]

I’m trying to decide if I want to try a flex tune. We don’t have enough e85 around my area that I’d be able to run exclusively ethanol, I’d like to be able to fill up with 93 when I need fuel and there’s no E around so a dedicated e85 tune that adds more timing down low is not an option.

I’m questioning if I’d really gain much of anything with a flex tune though? The 93 here is pretty sweet, and I see as much as 30*-31* at 7k RPM from my Lund 93 tune. I seem to recall reading that e85 tunes make about this much spark as well. So does e85 really offer a benefit over quality 93? If that’s the case, where does the extra power come from, if there is any? Or is it only a benefit for those who don’t have access to good 93? Or am I seeing a weirdly high amount of spark on 93? Any input?

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[Zelek]

I’m trying to decide if I want to try a flex tune. We don’t have enough e85 around my area that I’d be able to run exclusively ethanol, I’d like to be able to fill up with 93 when I need fuel and there’s no E around so a dedicated e85 tune that adds more timing down low is not an option.

I’m questioning if I’d really gain much of anything with a flex tune though? The 93 here is pretty sweet, and I see as much as 30*-31* at 7k RPM from my Lund 93 tune. I seem to recall reading that e85 tunes make about this much spark as well. So does e85 really offer a benefit over quality 93? If that’s the case, where does the extra power come from, if there is any? Or is it only a benefit for those who don’t have access to good 93? Or am I seeing a weirdly high amount of spark on 93? Any input?

It's about the same with flex as it is a 93 octane tune. It's when you mix in the ethanol that it gets better. I'm about to get my first flex tune here soon, but I have E85 near me. Occasionally, I'll go E85 for fun but mostly 93 octane.

93 octane tunes already factor in the 10% ethanol in most fuels so the flex tune won't be higher power on straight 93. I would just stick with your 93 tune.

 

[Blkbear17]

i have a lund flex fuel tune atm, ill tell you it stinks to high heaven but the car definitely feels stronger

 

[Bluemustang]

Yes. You will benefit from it. It's not all about timing advance. It doesn't always translate to more power. The high octane of E85 makes it virtually knock proof and you can also ramp up the timing much quicker. E85 also usually produces more torque which you feel down low. Possibly the best benefit is that it cools the intake charge which improves volumetric efficiency. And usually the engine will feel like it runs smoother.

 

[ManBearPig]

So a flex tune will ramp up timing quicker than 93? For some reason I was thinking it was only the dedicated e85 tunes that did that. But I can see that being a big benefit in increasing the “under the curve” pull

Is it weird that I see as much timing on 93 as some guys are seeing on e85?

 

[Bluemustang]

I saw 30* on 93 while using flex tune w/ the stock intake. After the 18 intake, only 26-27. But the power increase was great. So dont fuss over the timing advance.

 

[TeamHippo]

I can feel a noticeable difference between e85 and 93, it's not going to blow your mind but it's there. For me it was worth it and I personally love the smell when I crank my car up the garage.

 

[stangman638]

I finally put the flex fuel tune on mine, so far a bit underwhelming, reading 69% alc , but it doesn't feel any different than stock.

 

[armykyle1 [HACKED ACCOUNT]

Proper 93 tune will yield similar results to a flex tune. A true E85 tune will yield a decent power increase.

You can also look for a torco/boostane tune which will get you close to E85 tune results.

 

[nate-roth]

I can feel a noticeable difference between e85 and 93, it's not going to blow your mind but it's there. For me it was worth it and I personally love the smell when I crank my car up the garage.

The smell of catless E85 is bad ass in my book, smells like the tail pipes have vaporized cheap vodka. Its really pretty cool.

 

[yote41]

I don't believe you are seeing 31* timing with 93 and no additive. I have good 93 here and i max out around 18. My buddy with 93 and meth gets 22-24. All tuned by lund. Noway you get 30 something

 

[ManBearPig]

Yours sound like boosted values. I’m NA and routinely see 29-31* at WOT at 7k RPM with *good* 93. I have had tanks that would not advance beyond 26-27 before though.

 

[yote41]

I am boosted.

 

[Zelek]

Loaded flex tune last night. After about 15 minutes of idle and rev holding, I'm at 83.5% on Alch%. I feel a very noticeable difference over a straight 93 octane tune.

I'll be testing the E85R tune later this evening.

 

[DarkestHour]

It's not a huge difference on a naturally aspirated vehicle, but as already stated it is beneficial for being virtually knock proof. I run it during the summer to combat the heat. During cooler months, I just stick to 93.

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