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

[DJCarbine]

Yeah, having maxed out STFT until the ecu adapts is not my idea of an optimal situation.
Going flex fuel next summer with a zeitronix unit.

[jamesm]

Originally Posted by DJCarbine

Yeah, having maxed out STFT until the ecu adapts is not my idea of an optimal situation.
Going flex fuel next summer with a zeitronix unit.

You couldn't max the trim even if you put straight ethanol in your car, but yeah...

[post_break]

Originally Posted by Circuit Motorsports

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.


- Bob

Does he need to change it every time the car starts? Lets assume E85 is on map 2. Does the car start in the map it was last run in? So if he has E85 in the tank does he need to turn the car to on, switch to map 2, then start the car?

And the really scary part about this setup is when other people borrow your car. You run the risk of forgetting to tell them not to put fuel in the tank.

[s2d4]

Originally Posted by s2d4

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

I must have some invisible cloak on during the last 24 hours or something.

[DeliciousTuning]

Originally Posted by s2d4

I must have some invisible cloak on during the last 24 hours or something.

No you don't.

There are options outside of the oem ecu programming with Ecutek. Though I believe they are fairly expensive up front costs. Motec could be setup for FlexFuel but at the cost of over of nearly $5000 after the system and FlexFuel kits. I assumed we were only speaking about OE reprogramming systems. I apologize I should have clarified your original question.

[s2d4]

Originally Posted by DeliciousTuning

No you don't.

There are options outside of the oem ecu programming with Ecutek. Though I believe they are fairly expensive up front costs. Motec could be setup for FlexFuel but at the cost of over of nearly $5000 after the system and FlexFuel kits. I assumed we were only speaking about OE reprogramming systems. I apologize I should have clarified your original question.

All good, thanks for the clarification.

[DJCarbine]

Originally Posted by jamesm

You couldn't max the trim even if you put straight ethanol in your car, but yeah...

I would datalog it but I have no intention of fouling my plugs again. I'm just telling you what I experienced.

If you want to expand on why it wouldn't max the stft and that maybe I got a bad tune your post would be helpful in the context of the thread topic

[jamesm]

Originally Posted by DJCarbine

I would datalog it but I have no intention of fouling my plugs again. I'm just telling you what I experienced.

If you want to expand on why it wouldn't max the stft and that maybe I got a bad tune your post would be helpful in the context of the thread topic

because the difference in the amount of fuel required is less than the maximum correction allowed by the ecu. so, it'll just trim like crazy and be all over the place but you'll still see stoich afr at idle after it settles down, and if you drive around easy long enough to let the ltft settle in D, open loop will be reasonably fine. i'm not saying it's a great idea, just that 'maxing' the fuel trims would be an issue, and this doesn't happen in this case. wrx's with 15% trim caps are more likely to actually not hit targets due to density variation.

it takes a lot to convince this ecu to do something stupid.

[DJCarbine]

Originally Posted by jamesm

because the difference in the amount of fuel required is less than the maximum correction allowed by the ecu. so, it'll just trim like crazy and be all over the place but you'll still see stoich afr at idle after it settles down, and if you drive around easy long enough to let the ltft settle in D, open loop will be reasonably fine. i'm not saying it's a great idea, just that 'maxing' the fuel trims would be an issue, and this doesn't happen in this case. wrx's with 15% trim caps are more likely to actually not hit targets due to density variation.

it takes a lot to convince this ecu to do something stupid.

I was at -20% stft closed loop idle and the car would barely idle...
I was not interested in giving it time for the ltft to settle/adjust, as I don't like to rely on larger than necessary closed loop fueling adjustments

I believe the ecu can deal with a range of ethanol content, but I don't have to like how it deals with it when other options are available

Perhaps the tune was to blame... I got sent an e85 tune by mistake and suggested it to the tuner who verified that was the issue and an e10 "pumpgas" tune was sent in its place which had much more favorable initial trims

[jamesm]

Originally Posted by DJCarbine

I was at -20% stft closed loop idle and the car would barely idle...
I was not interested in giving it time for the ltft to settle/adjust, as I don't like to rely on larger than necessary closed loop fueling adjustments

I believe the ecu can deal with a range of ethanol content, but I don't have to like how it deals with it when other options are available

Perhaps the tune was to blame... I got sent an e85 tune by mistake and suggested it to the tuner who verified that was the issue and an e10 "pumpgas" tune was sent in its place which had much more favorable initial trims

Oh yeah it'll run rough until everything settles. My point is just that you won't max trims and not hit the afr target. That is a problem, just not with these cars.

[Circuit Motorsports]

Originally Posted by post_break

Does he need to change it every time the car starts? Lets assume E85 is on map 2. Does the car start in the map it was last run in? So if he has E85 in the tank does he need to turn the car to on, switch to map 2, then start the car?

You are correct. He is very aware of the need to switch to the correct map when running E85. Currently the car defaults to map 1 when starting and does need to be switched to map 2 if running E85. This is a change that has been requested from EcuTek to remember the last map run and a change I'd really like to see.

In this case, he only runs E85 on the track, and pump gas for street driving. He specifically did not want flex fuel. And I don't think he'll be lending this car out to anyone. So the chances of running on the wrong map are very slim.

Originally Posted by post_break

And the really scary part about this setup is when other people borrow your car. You run the risk of forgetting to tell them not to put fuel in the tank.

This is a great point and is why flex fuel is superior to straight E85 / pump gas tunes. With a flex fuel setup there is no need to remember to switch/flash maps, fill with the right fuel, etc. Although the same situation can occur on straight pump gas if you lend you car to someone who then fills it with 87 octane gas instead of premium.

Each owner/situation is different, but most folks I've worked and talked with and are looking to run E85/pump are car enthusiasts who are well aware of the fuel they run in their car and the tune they run on. The switch from straight E85 to pump and back is like a ritual at the pump and is not for the average car owner. Again, flex fuel makes the process idiot proof.

- Bob

[FA20Club.com]

Originally Posted by jamesm

because the difference in the amount of fuel required is less than the maximum correction allowed by the ecu. so, it'll just trim like crazy and be all over the place but you'll still see stoich afr at idle after it settles down, and if you drive around easy long enough to let the ltft settle in D, open loop will be reasonably fine. i'm not saying it's a great idea, just that 'maxing' the fuel trims would be an issue, and this doesn't happen in this case. wrx's with 15% trim caps are more likely to actually not hit targets due to density variation.

it takes a lot to convince this ecu to do something stupid.

Test your theory @WOT running a pump map on E85 and let us know your results in both NA and FI trim. Or moreso with a 60/40 blend or even a 50/50. Because Ive told many people in the past that is you run E85 on pump and didnt have time to swap maps your car will drive normally. But @WOT youll still be well short of your fueling needs. And besides the fact that your car can adjust fuel trims on the fly that doesnt help you when you blend varies by more than 10% fuel. Nor does it help you when you need to make significant timing adjustments based on an unknown amount of ethanol percentage. Running pure on either side of the blend isnt what this thread should be about. In some cases you will need to run a blend and will find yourself running a blend for whatever reason and always being able to have a safe basis of doing so. I have customers who drive their cars from across multiple states on a regular and find themselves mixing and matching fuels on their trips.

[FA20Club.com]

I think the major fact that needs to be covered isnt for those running pure on either end but those who have or want the ability to run a mixed ratio. We have our road/race cars running a specific blend reason being is it allows extending mileage in an enduro while getting us a bump in power. We are required to make "X" amount of pit stops but while doing so we must wait a total of alloted time before leaving. Being able to do the race while putting down enough laps without the additional pit stop helps allot. While flex fuel isnt mandatory foe all that doesnt mean it wont serve a purpose. Otherwise Audi, GM, Ford, Etc would never have spent the dollars it took to upgrade and add it to their vehicles. All we did is repurpose it for a performance specific application. Not only EcuTek But COBB, Hondata, Motec & Haltech have done this.

[FA20Club.com]

Originally Posted by Mars2

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

He has tuned a few of our kits over on his side.