yfz rock

I’m currently running ARH with weistec tune and drop In Filters I want to get a flex fuel kit and run e85 or a mix have been reading and some say you need bigger injectors are the factory’s running at 100% duty cycle?
anyone know if weistec supports bigger injectors with tunes or EC the only one?

AMGonFire

yes you need larger injectors 550 is ideal. As far as Weistec tune no idea but I’m sure they could tune for diff fueling like e85. In terms of running the flex kit you don’t necessarily need a tune when you have the flex kit. That’s the idea being able to change from 93 and e85 or mixtures of that when ever you want. Your car will automatically adjust timing to take advantage of the higher octane. A tune will net you more power on top of that. You would be looking at 15-20 wheel on e85 and another 10 to 15 with a specific tune for it.

yfz rock

I was told I would need a new tune because of the bigger injectors not the flex fuel part of it.

blurred

Yes, you need to tune for the various mixes of ethanol and gasoline. Flex fuel simply allows for blend ranges so that you can simply pump whatever you like and you will be tuned for it (instead of loading an e40 tune, then an e60 tune etc). Otherwise you would need to be within 5% or so.
Also if you change injectors, yes you need to fully tune for that.
Ethanol has a different stoich ratio so your car cannot automatically adjust for it as at e85+ you need to use about 30-40% more fuel so your afr will be extremely lean without a tune.

AMGonFire

ok no your wrong. You don’t need a tune if you have a flex kit. I have had eurocharged flex kit also known as fluid dynamics kit for 3 and a half years with 550 cc injectors. I think I know what I’m talking about. I also have headers and catless mids. The reason you don’t need a tune is because the flex box adjusts the fueling based on the ethanol reading it receives. This is the benefit you can run whatever blend you want. I run full e85 all the time. Except in the winter when my car sits in the garage. I add an ethanol additive every fuel up too. I have an e85 tune however I typically just run my normal 93 euro charge tune no issues what so ever. There are some cars that auto change the tune based on 93 vs e85. This is not one of them. You can run e85 with out a flex kit however your tune needs to be spot on fueling wise and you better know your exact E number. The flex kit simplifies everything and gives you more flexibility. I would recommend not getting the cheaper kits guys buy. Those are the only ones I’ve seen people have issues with. Contact eurocharge atx for the kit. Haven’t had any issues with mine.

blurred

Most flex fuel kits are just a flex sensor and plumbing and still require a full tune (still the best option). Your vehicle specific kit came with a "flex box" which is a piggyback tuner... so yes not only do you have a tune (not an ecu tune, but a piggyback) but it is also very important to mention.

AMGonFire

again you are wrong. All of the kits available for our cars are essentially the same. The sensor detects the amount of ethanol. Sends that back to the box. The box is only connected to the injectors. It changes the percentage of fueling based on the amount of ethanol automatically. There is no tune. It is ensuring you don’t run lean. Ethanol requires 30 percent or so more fueling. It’s very simple. The box is not a piggyback tune that is hooked up to other various sensors in the car. Your car ect has full control. No trickery like a piggyback. Op trust me you will be fine if you contact eurocharge atx.

doncmleon

Read through these threads and you'll see that AMGonFire is correct

https://mbworld.org/forums/c63-amg-w204/781803-e85-preparedness.html

mbworld.org/forums/c63-amg-w204/651192-flexfuel-everyone-eurocharged-atx-e85-kits-now-available.html

blurred

Yes, seems like there are some full kits out there with a piggyback fuel controller already included. We simply have never bought "kits" before and all our cars we just add the flex sensor and then tune it on the dyno. If I was to go flex fuel I would still do it this way because my friends are all fabricators and tuners so I don't need to look at kits. These look great for the diy'er who wouldn't be able to build the kit from scratch themselves.

AMGonFire

yes this can be done on our cars too. It’s just more of a pain to make sure you have the exact ethanol percentage in the car each fill up that you are tuned for. You can tune for e85 with these kits as well.

doncmleon

yup my next step (Full E85 Tune).. thankfully, i have a VP Racing station right be the home, so availability isnt an issue. Plus its not a daily driver

roadtalontsi

I really don't understand E85 on m156 N/A cars. That's a lot of work and headaches for 20whp.

yfz rock

lol it’s really not much headers are A lot of work and money for the gains

AMGonFire

not really took me an hour and a half to install the kit and injectors. Pretty easy really. Then pump in e85. Not hard at all.

sunnys14

For a basic $350 Eflexfuel kit, you can gain as much or even more than a $2000 Renntech intake system.

doncmleon

Yep, did mine as well. Took me a little longer because i did some collateral maintenance work (I'm very **** about a clean engine bay) ..so over all about 2.5 hours. (Cleaned injector ports REALLY good, Upgraded injectors, kit install,) Even ran the kit so clean you can barely tell it's there.

Cut my fuel costs in almost half, got some good power. No doubt I'd do it again

PeterA90

Both eflex and AFD kits do the same thing. If you hook up the kit with your base tune you will gain 10-15whp peak at best. If you tune for e85 you can get 30+ peak and 35+ under the curve. And a **** ton of tq. Which would put this car pretty close to 500whp n/a dependent on how good your tune is.

You also don’t need to contact eurocharged for a kit. All they are gonna do is add 250+ dollars on top of the kit with injectors. The injectors you seek are part number 0280158123

Just make sure your kit has EV1 harness connection

Side note your fuel trims will never be correct. Those kits don’t run very well. 80-85% at best. When your trims aren’t correct you’ll lose power.

Also, it’s not hard to monitor your e content. All you need is a sensor and gauge. If your tune is meant for e75 and you have e60... you will have knock and detonation. There’s really no point in running race gas running 93 timing. Waste of time, I’ve done it.

if you want more power than that you’ll need nitrous or supercharger

roadtalontsi

The install is not what i'm referring to. E85 is highly corrosive, pump e85 highly inconsistent, collects moisture rapidly if the car sits and requires much more frequent oil changes. Things i wont be sacrificing for 30hp, or even more considering I have a blower and much more to gain.

As the guy above mentioned. Fuel trims will always be wrong. that's a hard pass.

PeterA90

E85 will dry out the injector nozzles as well. So a bottle of fuel injector clean is recommended every 1200 miles or 4th-5th fill up. Oil changes regardless of running e85 or not should be done at 4-5k miles on the m156 especially if driven hard. As long as you monitor your e content. You can have a tuner build you multiple mixture files. If the car is full on gas it won’t collect as moisture as some may think.

On your supercharger you greatly benefit from even an e30 blend. I’d be surprised if you didn’t get 30+whp without even tuning the car. Full e85 FI cars gain 70+ with proper tuning and fuel support.

As I said before, e85 on the car with no tuning will feel lackluster. The Bosch computer is going to be fighting itself to correct trims. This will lead to inconsistency on how the car feels. Also, e85 will require much more timing because of the burn rate. Most wont understand this car their car might drive fine. But go against a properly tuned car and you’ll be surprised.

Also, the people who have trouble in cold start with e in colder weather is because your cold start fuel map needs to be rebuilt. Eurocharged, weistec, oetuning, does not offer that. They simply change the load tables, add 3-4 degrees of timing everywhere and hopefully the Bosch takes care of the rest.

Custom tune, headers, e85 will yield phenomenal results for an N/a car.

C63AMGeez

If I understood this correctly if one decides to tune for e85 for max gains, ideally you'd need multiple tune files for different levels of e content to avoid issues? Since it sounds like all e85 stations are inconsistent.

PeterA90

yes you need different map timing for the e content you are running. You can’t run e75 timing only running a blend of e60. This obviously isn’t a set it and forget it type of ordeal. That’s why some prefer the flex kit because it’s just fill up and go. It doesn’t adjust timing, trims etc. all it does is adjust the duty bias for e content. Similar to what a piggyback does.

todthedod

Just to add I have a flex fuel kit that I"ve been running for 80k miles with no issues. Usually find E70 around here. Only things I can tell is a little hard to start on cold mornings and an extra 5 car gap on cars I usually only gap by one.