FlexFuel over Straight E85 on EcuTeK, why is it better?

[DeliciousTuning]

There is a lot of debate on whether you really need FlexFuel over runnign straight E85 and in my opinion it is FlexFuel is much safer and more reliable versus the alternative of straight E85 or shall we call it Emix? Here is s little article on E85 / Alcohol and the good/bad with it by Paul Yaw of Injector Dynamics.

Everything You Never Wanted to Know About Alcohol

ASTM D5798-11 Standard Specification for Ethanol Fuel Blends for Flexible-Fuel Automotive Spark-Ignition Engines
"The original specification set the minimum ethanol content at 75% which was lowered to 68% in June of 2010, and lowered again to 51% in June of 2011. As of February 2012, this is the current specification and E85 purchased from the pump could have an ethanol content as low as 51% and still be within spec."

From this small bit of information (quoted above from the article link) we know that filling up at any time, at any pump the content of ethanol can change and range anywhere between the mythical 85% ethanol to as low as 51% ethanol. Now what impact does this have on tuning? This can cause any vehicle running a non-FlexFuel setup potentially run rich and far too much timing which can lead to obvious problems. Now even on a conservative tune where the E85 becomes a E75 the tune will more than likely be within spec but a change to E60 can definitely cause problems. So as long as you are testing the E85 on a regular basis, you really are not sure to the content mix of E85.

Now with EcuTeK RaceROM running FlexFuel, the timing, fueling and boost can all be calculated based on the reading from the FlexFuel sensor so you know it is within spec and the car is tuned properly for whatever mix is in your tank.

Here are some example information on how EcuTeK's FlexFuel is setup through RaceROM custom mapping.


Image #1


Image #2

Notes on EcuTeK RaceROM Custom Mapping
- As you can see these are custom maps in EcuTeK RaceROM, more than just the standard features available such as launch control, auto-blip, etc...
- These maps allow you truely create new maps based on X and Y inputs channels and an output channel.
- X and Y Input channels are listed in Image #2, along with the optional output channels.

Notes on FlexFuel RaceROM Custom Mapping (Map A)
- X channel input as Engine Speed (radio button X channel image #2)
- Y channel input as CPC Pressure Sensor (radio button Y channel image #2), a wire used on the OEM harness
- Output Channel is a "Calculation Only" used in Input Channel on other custom maps (such as Map C in Image #1)

Notes on FlexFuel RaceROM Custom Mapping (Map C)
- X channel input as Coolant Temp (as seen in image)
- Y channel input as calculated result from output channel on Map A
- Output Channel is a multiplication factor of the total fuel quantity, so as E85 becomes more pure the fuel quantity increases accordingly.

Additional FlexFuel RaceROM Custom Mapping Tables
- Ignition Timing based on the calculation from the calculation from Map A
- Cranking Enrichment for cold and hot starts, so the vehicle starts even in the coldest climates.
- And of course a lot more can be added, such as dynamic boost control and dynamics cam control

With all these features from EcuTeK you can have a true FlexFuel system in your vehicle that will run consistent without having to check the content of E85 ever again. Just fill up, drive and go.

Regards,
William Knose

[Malt]

Originally Posted by DeliciousTuning

...
ASTM D5798-11 Standard Specification for Ethanol Fuel Blends for Flexible-Fuel Automotive Spark-Ignition Engines
"The original specification set the minimum ethanol content at 75% which was lowered to 68% in June of 2010, and lowered again to 51% in June of 2011. As of February 2012, this is the current specification and E85 purchased from the pump could have an ethanol content as low as 51% and still be within spec."
...

Is this a country wide issue as the pump I fill up at states a minimum of 70% of ethanol? I haven't personally tested the ethanol content but based off the LTFT's my car is running and the cold starting issues with a straight E85 tune I'm guessing the ethanol content is actually higher than 85%.



Obviously a true flexfuel setup is ideal and that is one of the nice things that ECUtek has going for it right now.

[DJCarbine]

Originally Posted by Malt

Is this country wide as the pump I fill at states a minimum of 70% of ethanol? I haven't personally tested the ethanol content but based off the LTFT's my car is running and the cold starting issues with a straight E85 tune I'm guessing the ethanol content is actually higher than E85.

I read this earlier

http://ethanolproducer.com/articles/...-to-51-percent

Maybe the sticker on the pump is old?

I would get an ethanol content tester regardless, it never hurts to know how much

[jamesm]

Originally Posted by DJCarbine

I read this earlier

http://ethanolproducer.com/articles/...-to-51-percent

Maybe the sticker on the pump is old?

I would get an ethanol content tester regardless, it never hurts to know how much

i've found that the local content has gone from around 78% down to around 73% in the time i've been running e85. i haven't had to make any adjustments for it, fuel trims just average up or down a bit depending on the blend.

if you ask me what makes me most jealous about this setup is the ability to change boost based on ethanol content. i really want that , though the rest is nice to have as well it's more of a convenience thing saving you from checking trims occasionally (which i'd do regardless).

i could think of about a billion other ways i'd like to use that software though . it's like the poor man's motec build ecu lol. they'd really have something to sell there..

[FA20Club.com]

Down here in South Florida we are currently getting lower end of the spectrum for our yearly blend of low 70s. The ability to vary boost output is one thing Ive been implementing lately. Makes thing fool proof when you have customers that forget to adjust their boost accordingly. This of course is for those using Ecutek boost control.

[post_break]

I have filled up after hitting E87 with the flex fuel and had it dive bomb to E60. Same gas station. It really does vary pump to pump.

[SmsAlSuwaidi]

Even though i plan on running e85 90% of the time, a flex fuel sensor is a must for me just because i feel its safer to have

[Mars2]

Delicious do sell the hardware for flex fuel or only the tune?

[s2d4]

Is ecutek the only solution that will do flex fuel?

Have you utilised the fuel temperature output from the zeitronix ECA to cater for variations from hot to cold climate?

[DeliciousTuning]

Originally Posted by Mars2

Delicious do sell the hardware for flex fuel or only the tune?

I currently sell only the tune but working on my own hardware kit. This should be available in the next couple months with cool new features.

Originally Posted by s2d4

Is ecutek the only solution that will do flex fuel?

Have you utilised the fuel temperature output from the zeitronix ECA to cater for variations from hot to cold climate?

Currently EcuTeK is the only solution for FlexFuel on these vehicles. As for the temperature I have not used it from the Zietronics but there is a probe in the tank that also reads the fuel temperature that is used in the ECU.

Cheers,
William Knose

[Circuit Motorsports]

As you can see, a flex fuel setup is safer and more reliable than a straight e85 tune due to the wide variance of the e85 blend.

Having said that, a recent customer specifically requested a straight E85 tune for track use, and a straight 93 pump gas tune for street driving.

Using EcuTek software and its custom map capability made tuning for E85 fairly straight forward. You are able to leave the injector scaling true and pure to the injector size (850cc injectors would still be scaled to 850cc). Using the custom maps you can request the additional fueling, and add compensations to that fueling based on any number of data including temperature, as well as compensations for cold start cranking. And of course using the input from an ethanol content sensor gives you full flex fuel capability.

An added benefit to my E85 customer is EcuTek's map switching, creating the ability to switch from E85 mode to 93 pump gas mode with a flick of his fingers on the cruise control stalk. No flashing required, no laptop, no hand-held device or other hardware required.

So, along with the flex fuel capability, you have seen just the surface scratched in what can be accomplished with EcuTek's custom map feature -- far beyond just launch control, flat foot shifting, etc.

- Bob

[DJCarbine]

As someone who accidentally flashed an E85 tune when running E10, the car will barely start/idle on the E85 map and the factory "wideband" was pegged rich.

Flexfuel compensation is a good thing.... why rely on LTFT to adjust your trims depending on the ethanol content when you can do a much better job with an ethanol analyzer and fill with whatever you please

[s2d4]

Originally Posted by DeliciousTuning

Currently EcuTeK is the only solution for FlexFuel on these vehicles. As for the temperature I have not used it from the Zietronics but there is a probe in the tank that also reads the fuel temperature that is used in the ECU.

What about motec, or the other standalone/semi-standalones?

[DeliciousTuning]

Fun Facts:

1. FlexFuel as defined by the US Government.

Flex Fuel Vehicles

"Flexible fuel vehicles (FFVs) are designed to run on gasoline or a blend of up to 85% ethanol (E85). Except for a few engine and fuel system modifications, they are identical to gasoline-only models. FFVs experience no loss in performance when operating on E85. However, since ethanol contains less energy per volume than gasoline, FFVs typically get about 25-30% fewer miles per gallon when fueled with E85.1"

2. Can a tuned FlexFuel vehicle run on E85 fuel? Yes
3. Can a tuned E85 vehicle run as a FlexFuel vehicle? No

Originally Posted by DJCarbine

As someone who accidentally flashed an E85 tune when running E10, the car will barely start/idle on the E85 map and the factory "wideband" was pegged rich.

Flexfuel compensation is a good thing.... why rely on LTFT to adjust your trims depending on the ethanol content when you can do a much better job with an ethanol analyzer and fill with whatever you please

You bring up a very good point as I stated earlier small changes will adjust within the ECU especially for fuel but more drastic changes can have an impact as you have stated in regards to fueling.

Would you fill up your minimum rated 91 octane vehicle with 87 octane? Why not it is only a small difference of 4 octane points? Think about that, what is the concern? The ignition advance, timing, whatever you want to call it. A naturally aspirated FA20 engine with 12:1 compression is potentially more prone to knock events versus say a 8.2:1 compression Subaru STI Engine. As we have seen in knock corrections on many stock FA20 based vehicles, the Advance Multiplier will adjust in large steps due to the inconsistency at the pumps. So would you fill up the random ethanol fuel of the day?

I personally prefer to create a map that gives the optimal performance of the vehicle while taking advantage of as many compensation tables as possible so that the ECU can calibrate itself to the conditions known by the vehicle's sensors. In my personal opinion auto corrections (correcting for incorrect fuel mixtures, timing values and boost levels) are a way of being lazy and potentially damaging a customers vehicle when relying on those built in safety features. These should be used as systems to protect the engine when needed, not as a way of tuning.

Example: Ken Block Gymkhana 1 Subaru

Ken asked during the filming if he could bounce the vehicle off the rev limiter under full throttle? (That was 8000 RPM) I said sure and he proceeded to gymkhana his Subaru around the segway and I suggest you check out the marks on the tarmac in that video.

When he came in, I pulled out my EcuTeK software plugged into the ECU and checked the Advance Multiplier which we all hope to see at 1.00. Well it wasn't, it was at 0.85. I was personally a little upset it was not at 1.00 but also amazed the ran flawlessly for him and glad those safety features protected the engine to the abuse it was put through.

Cheers,
William Knose