[stewbets]

Originally Posted by Achappell8

I never understood this e85 obsession. Why would anyone run fuel that is harder to get and less than potent than 87. I prefer to run 93 in my car - highest octane and readily available at any Shell station.

It is not less potent than 93, much less 87. It has substantially more power potential than 93 due to its much higher octane rating, albeit at a lower fuel efficiency. The 85 does not refer to its octane rating. It's more like 105 octane.

[Oembmw]

Originally Posted by Achappell8

I never understood this e85 obsession. Why would anyone run fuel that is harder to get and less than potent than 87. I prefer to run 93 in my car - highest octane and readily available at any Shell station.

I've heard of that as well! 93 or higher is a little bit harder to get here in LA

I wouldnt mind running a higher octane to see what thats like and explore the platform further.

I can run 93 on the stock LPFP, right? What about even higher octanes like race gas. what would be the bare minimum mods for that?

[RnmEvo9]

Originally Posted by Achappell8

I never understood this e85 obsession. Why would anyone run fuel that is harder to get and less than potent than 87. I prefer to run 93 in my car - highest octane and readily available at any Shell station.

Is this an early April fools joke?

[Oembmw]

Originally Posted by Aceway

Upgraded lpfp, upgraded line from hpfp to fuel pressure regulator, and tune is all you need. Downpipe heavily recommended. MHD would probably be easiest. If your hpfp is in good condition you won't need port injection, but running without PI will accelerate wear on the pump. Bare minimum doesn't make sense cause most people run full e85 for power but who cares if that's what you wanna do I guess.

OH OK so the port injection decreases the stress on the HPFP.

& what is that upgraded line? do you have a link to that part online?

Thanks man!

[stewbets]

Originally Posted by Aceway

Upgraded lpfp, upgraded line from hpfp to fuel pressure regulator, and tune is all you need. MHD would probably be easiest. If your hpfp is in good condition you won't need port injection, but running without PI will accelerate wear on the pump. Bare minimum doesn't make sense cause most people run full e85 for power but who cares if that's what you wanna do I guess.

No need to upgrade the fuel lines. The HPFP becomes the bottleneck with full e85 because of high boost and high HP requiring so much more fuel on top of e85 being 30% less energy dense than 93. But since it sounds like he just wants an economy tune designed around e85, his HPFP should be just fine.

[Aceway]

Originally Posted by Oembmw

OH OK so the port injection decreases the stress on the HPFP.

Thanks man!

Only on stock turbos. PI is needed for the extra fuel required when going beyond stock turbo power levels.

[stewbets]

Originally Posted by Oembmw

What other mods will I need for the custom tune?

MHD or JB4? and then just contact a custom tuner?

Yes, MHD would be the easiest route. The first step would be to find a tuner willing to make an economy tune designed around e85. Like others have mentioned, e85 won't be cheaper to run. People run it because it has substantially higher power potential.

[stewbets]

Originally Posted by Aceway

Oh I always thought there was something about e85 that corroded stock lines but it's a pressure thing?

People were afraid of that in the beginning. It hasn't been the reality, though. I consider that warning as roughly equal to the necessity of installing matching injector indexes in each bank. It sounds legit, but it doesn't really matter.

[Oembmw]

Thanks for all the replies everyone!

[ab987]

Originally Posted by Saif2018

lol, the only way you would get better mpg on a N54 compared to M52/M54 or N51 is if those engines had problems

These can get pretty efficient, I can get 30mpg on the highway tuned on big twins and average low 20s in the city, my brother's 328i n52 gets only marginally better on the highway and less in the city. Another friend with a 330i N52 (metal top) gear mid 20s on the highway and averages high teens. I wouldn't be too surprised

[FireBlaze]

I’m running E30 map now… it would be more convenient to not have to mix gas. California has lots of E85 stations and you can flash to a gas map if I’m ever desperate.

[Saif2018]

Originally Posted by ab987

These can get pretty efficient, I can get 30mpg on the highway tuned on big twins and average low 20s in the city, my brother's 328i n52 gets only marginally better on the highway and less in the city. Another friend with a 330i N52 (metal top) gear mid 20s on the highway and averages high teens. I wouldn't be too surprised

He's got problems with his car if that's the case, N54 drinks more than the M54/N52,

I had them previously and could easily get 30mpg or more highway. Even BMW lists them as having better fuel efficiency than the N54 although marginally.

On the highway, cruising N54 is pretty good, but city driving can be terrible, driving frequently on boost the N54 tanks the fuel efficiency. I don't know how it is in US but UK traffic can be gridlocked, or constant moving off and stopping at at traffic or lights at lower gears. It can drop to high teens.

Saying all of the above, I didn't buy a N54 for fuel efficiency. There are loads of other cars that have way better fuel efficiency for similar price, unfortunately most of them are slow miserable bangers lol.

[mj6234]

If you just want to run E85 for cost and not performance, you don't need much. LPFP upgrade and custom tune to adjust the fuel scalars is really the minimum if you wanted to just run stock boost.

But if you are going to mix fuels and bounce between them, I would get the Motiv Flex Fuel module so you dont have to reflash to adjust the scalars and wonder about the mix in the tank.

[lookalikehuuh]

Originally Posted by Oembmw

I've heard of that as well! 93 or higher is a little bit harder to get here in LA

I wouldnt mind running a higher octane to see what thats like and explore the platform further.

I can run 93 on the stock LPFP, right? What about even higher octanes like race gas. what would be the bare minimum mods for that?

I take it he has no experience with E85 and therefore doesn't really understand the benefits and actual cost savings over gasoline in California specifically. As someone that actually runs it on one of my cars let me give you my perspective:

1. MPG. Yes E85 does give you lower MPG in my true to life experience, I have lost about 2-3mpg on the same car. If I make lots of short drives and stop/go city driving I can average about 17MPG and all highway I average about 22MPG on E85.

2. Cost. Forget about them comparing it to 87 etc because none of that shit matters or is realistic. Our cars require 91 so it is only fair to compare to 91 prices. Right now at my local shell 91 is currently $6.49/gal The same station sells Pearson fuels E85 for $3.39/gal.

Simple math: Cost to fill E85 today: ~$52. Cost to fill 91 today: ~$100
It is literally 48% cheaper in SoCal to fill up with E85 vs 91 today and has been like this for some time.

3. Octane. Average octane rating of ACN91 (this is the "Arizona/California/Nevada 91" is closer to ~90 octane rating). E85 in socal averages ~E80-E82 year round in my own testing for over 2 years. This equates to somewhere in the range of true 100-104 octane. This much higher octane reduces ping, allows for additional timing to be ran on the tune, and increases torque/horsepower.

4. Performance. As stated above the much higher octane rating provides way more tune-ability potential including increased boost, timing etc.

5. Availability. I'm not going to pretend I know what availability is where you live but in SoCal you can download the Pearson Fuels app that lists the location and price of E85 in your area. I personally have more than 12 fuel stations with E85 available within a 10 mile radius of my house. Its really not that difficult to find, plus I always fill up around the 1/4 tank mark so I always have plenty of range to spare.


last thing to note, you mentioned trying to get 93, according to your location you are in socal, which means getting 93 is not practically possible unless you are going to drive to another state every time you need to fill your tank. I supposed you could get ACN91 up to a 93 rating by mixing in 100 octane racing gas but in my experience only the VPRacing fuels locations have 100 octane gas and it costs like $15+ a gallon.

[R3dLeader]

What about mixing some ACN 91 with E85 to bump the octane a bit and run a 93 octane MHD file?

[ky0u]

Originally Posted by lookalikehuuh

last thing to note, you mentioned trying to get 93, according to your location you are in socal, which means getting 93 is not practically possible unless you are going to drive to another state every time you need to fill your tank. I supposed you could get ACN91 up to a 93 rating by mixing in 100 octane racing gas but in my experience only the VPRacing fuels locations have 100 octane gas and it costs like $15+ a gallon.

I was about to point out this exact thing. We top out at 91 here in CA. And even that is like Diet 91. We run e-blend to "cheat" our way to higher octane wihtout having to shell out for race gas.

OP, if youre running pump gas, be it 91, 93, 100 etc, there's no need for LPFP upgrade (unless youre custom tuned to run a much higher flow of gas for some reason). The reason for LPFP upgrades is that ethanol contains less energy than gasoline. So it requires higher volume of fuel to operate. When you run over 30% ethanol in our cars, this demand is too high for the stock fuel pump to deliver and it crashes. This is also why port injection is needed to run higher to full ethanol content

Also, FWIW, a pump gas stage 2+ tune will ramp the boost up enough to fairly close to the limit of the stock turbos. If you're running full e85 and tuned for performance, those turbos will definitely become a weak link in your build. Also, most people go FBO before messing with ethanol, I would reconsider doing the bare minimum if youre planning on going full e85.

[ky0u]

Originally Posted by R3dLeader

What about mixing some ACN 91 with E85 to bump the octane a bit and run a 93 octane MHD file?

I ran e25 with that set up a year ago and got lean errors.

[lookalikehuuh]

Originally Posted by R3dLeader

What about mixing some ACN 91 with E85 to bump the octane a bit and run a 93 octane MHD file?

According to my calculations that would need to be somewhere around E26 or E27 assuming E83 and E10 for gasoline.

At that point you should just run the E30 OTS map that will more properly target the proper fuel mixture for E85 requires.

This is because E85 has an oxygen component as part if its atomical makeup

[Achappell8]

Originally Posted by RnmEvo9

Is this an early April fools joke?

Yes 😂 trolling.

[whyzee125]

You can run full e85 on a stock car with just MHD, a custom tune, and a stage 3 fuel pump. That being said, the main reason for running full e85 is more power, and if you tune for more power, you'll need a lot of other mods.

To take advantage of the power gains you couldn't get on pump gas, you'll need a stage 3 LPFP, port injection, a PI controller (AIC-6 or similar), and upgraded fuel lines. Fuel it, MMP, and I believe a few others have what you need.

[cruizinmax]

A lot of internet geniuses here just repeating why they "heard."

What "I" have in my car is just a walbro 450, intercooler, charge pipe, downpipes, flex fuel sensor and a motiv ECA, and OTS flex fuel maps. You could get away with just a tune and a walbro 450. An intercooler and charge pipe would be preferable for reliability. Definitely no port injection, stage 3 fuel pump, fuel line replacements are necessary.

[studio54]

Originally Posted by cruizinmax

A lot of internet geniuses here just repeating why they "heard."

What "I" have in my car is just a walbro 450, intercooler, charge pipe, downpipes, flex fuel sensor and a motiv ECA, and OTS flex fuel maps. You could get away with just a tune and a walbro 450. An intercooler and charge pipe would be preferable for reliability. Definitely no port injection, stage 3 fuel pump, fuel line replacements are necessary.

Well, another one