[Joshinator99]

Originally Posted by arpad_m

Do you understand what he meant by "tuned" E60 vs "flex fuel" E60? There is no difference on this platform, you have to tune the car if you want to use >10% ethanol...

Are you talking to me or him lol? I explained up above how this car is not like the Mustangs that must be tuned to your ethanol content on a boosted engine. Our cars use the flex sensor as I also mentioned.

Who’s on first?

[arpad_m]

Originally Posted by Joshinator99

Are you talking to me or him lol? I explained up above how this car is not like the Mustangs that must be tuned to your ethanol content on a boosted engine. Our cars use the flex sensor as I also mentioned.

Who’s on first?

You I genuinely don't understand his question and it seemed you did, hence mine.

These terms ("tuned" and "flex fuel" E60) make no sense to me... as far as I know, E60 is E60 and this ratio of ethanol to gasoline comes with higher fueling requirement, plus the stoich tables are not populated (they're set to 10% ethanol across the board) by default, so tuning is a necessity no matter what.

So while I know how our cars work for the most part, but thought maybe I missed something and you had extra insight here.

[Joshinator99]

Originally Posted by arpad_m

You I genuinely don't understand his question and it seemed you did, hence mine.

These terms ("tuned" and "flex fuel" E60) make no sense to me... as far as I know, E60 is E60 and this ratio of ethanol to gasoline comes with higher fueling requirement, plus the stoich tables are not populated (they're set to 10% ethanol across the board) by default, so tuning is a necessity no matter what.

So while I know how our cars work for the most part, but thought maybe I missed something and you had extra insight here.

Ah, OK. Let’s try this regarding being “tuned for E60”: Many cars cannot use a flex sensor and are tuned specifically for whatever fuel they’re going to use. For example: The Mustang has a built in wideband and can slowly compensate for changes in ethanol content WITHOUT a flex sensor. It’s called Inferred Fueling. But, this doesn’t work on a boosted engine since the fueling needs are greater and immediate. If you ran 93 all day, filled up with E85 in your Gen3 Coyote, then immediately went WOT you’d possibly smoke then engine since it didn’t have enough time for the Long Term Fuel Trims to catch up with the fact that you’re now running lean. And the Coyote doesn’t compensate timing based on E content which is a problem if you tune for E and decide to run 93…. SO, on a boosted Coyote, you either run a 93 tune or an E tune based in what your fuel system can handle. My brothers twin turbo ‘23 GT has an E-specific tune. He loads a 93 tune in the rare case he runs 93. Hope that makes sense. If your Coyote can only run E60 max due to limitations in fuel volume, then you tune your car specifically to E60 on the dyno since it’s not able to really compensate for, say, E85 very quickly on the fly.

On the Camaro, adding the sensor and tune is truly a “flex” tune since the ECM can see exact ethanol content and alter BOTH the desired fueling AND timing advance on the fly. It’s a big difference. I love the Mustang wideband and DI/Port injection, but the Camaros ability to run a flex sensor is pretty sweet, especially if you’re not always running the same fuel or ethanol content.

Any other questions, fire away.

[KingLT1]

Originally Posted by FlukeSS

You mention you run E60. Is that a tuned E60, or a flex fuel E60?

I'd rather stay away from a tuned E content, would rather stick with flex fuel if possible.

Flex fuel. E60 is as high as I go.

[arpad_m]

Originally Posted by Joshinator99

Ah, OK. Let’s try this regarding being “tuned for E60”: Many cars cannot use a flex sensor and are tuned specifically for whatever fuel they’re going to use. For example: The Mustang has a built in wideband and can slowly compensate for changes in ethanol content WITHOUT a flex sensor. It’s called Inferred Fueling. But, this doesn’t work on a boosted engine since the fueling needs are greater and immediate. If you ran 93 all day, filled up with E85 in your Gen3 Coyote, then immediately went WOT you’d possibly smoke then engine since it didn’t have enough time for the Long Term Fuel Trims to catch up with the fact that you’re now running lean. And the Coyote doesn’t compensate timing based on E content which is a problem if you tune for E and decide to run 93…. SO, on a boosted Coyote, you either run a 93 tune or an E tune based in what your fuel system can handle. My brothers twin turbo ‘23 GT has an E-specific tune. He loads a 93 tune in the rare case he runs 93. Hope that makes sense. If your Coyote can only run E60 max due to limitations in fuel volume, then you tune your car specifically to E60 on the dyno since it’s not able to really compensate for, say, E85 very quickly on the fly.

On the Camaro, adding the sensor and tune is truly a “flex” tune since the ECM can see exact ethanol content and alter BOTH the desired fueling AND timing advance on the fly. It’s a big difference. I love the Mustang wideband and DI/Port injection, but the Camaros ability to run a flex sensor is pretty sweet, especially if you’re not always running the same fuel or ethanol content.

Any other questions, fire away.

Got it, thanks a lot. I didn't know the Mustang had no sensor and used solely the fuel trims to try and adjust for E content.

So then "flex fuel E60" refers to this slow and limited fuel ramp up/ramp down capability on other platforms, while "tuned E60" means the tune is adjusted specifically to this content, including timings (but then you can't run 93 anymore on the same tune).

Beats me why a manufacturer would build a car with very limited, software only adjustment to alcohol content when a sensor only costs a couple bucks, but then again I'm still surprised at the lengths they go to save a darn penny everywhere [while paying $50-60 for assembly line work].

[FlukeSS]

Originally Posted by arpad_m

Got it, thanks a lot. I didn't know the Mustang had no sensor and used solely the fuel trims to try and adjust for E content.

So then "flex fuel E60" refers to this slow and limited fuel ramp up/ramp down capability on other platforms, while "tuned E60" means the tune is adjusted specifically to this content, including timings (but then you can't run 93 anymore on the same tune).

Beats me why a manufacturer would build a car with very limited, software only adjustment to alcohol content when a sensor only costs a couple bucks, but then again I'm still surprised at the lengths they go to save a darn penny everywhere [while paying $50-60 for assembly line work].

This is what I meant, and what Josh said.

[Joshinator99]

Originally Posted by arpad_m

Got it, thanks a lot. I didn't know the Mustang had no sensor and used solely the fuel trims to try and adjust for E content.

So then "flex fuel E60" refers to this slow and limited fuel ramp up/ramp down capability on other platforms, while "tuned E60" means the tune is adjusted specifically to this content, including timings (but then you can't run 93 anymore on the same tune).

Beats me why a manufacturer would build a car with very limited, software only adjustment to alcohol content when a sensor only costs a couple bucks, but then again I'm still surprised at the lengths they go to save a darn penny everywhere [while paying $50-60 for assembly line work].

Great, glad my explanation made sense. If you could take the best from both manufacturers and put it together you’d really have a badass ride!

Originally Posted by FlukeSS

This is what I meant, and what Josh said.

[KingLT1]

Flex fuel means exactly what it sounds like. You can run pump gas or any blend of Ethanol up to 85% and the ECM automatically accounts for the change. When you see guys running boost say E60, that usually means the cap or max amount of Ethanol they can run to keep the fuel system happy. You can run less or even pump gas still. GM is one of the few manufacturers that actually have flex fuel ECMs. As Josh mentioned Ford performance stuff like the Coyotes do not have flex fuel capability. Nor does Mopar for the Hellcats. However, there are some piggyback solutions that allow for it otherwise you have to hard tune for the fuel Meaning adjust stoich ratio in the tune and only run that fuel. It's still not that hard to do if you have a Laptop. I know some of the older GM cars( F bodies ) do it that way. If you don't drive it every day it's not really a big deal. Takes all of 5 minutes to figure out what your E content is and flash the correct Stoich value in the tune.

I am just curious why Fluke would assume you lose "Flex fuel" when going to Forced Induction? I think that is what started this confusion. You don't lose anything, but it's a good chance you might have to blend the Ethanol percent down by mixing in more pump gas.

[FlukeSS]

Originally Posted by KingLT1

Flex fuel means exactly what it sounds like. You can run pump gas or any blend of Ethanol up to 85% and the ECM automatically accounts for the change. When you see guys running boost say E60, that usually means the cap or max amount of Ethanol they can run to keep the fuel system happy. You can run less or even pump gas still. GM is one of the few manufacturers that actually have flex fuel ECMs. As Josh mentioned Ford performance stuff like the Coyotes do not have flex fuel capability. Nor does Mopar for the Hellcats. However, there are some piggyback solutions that allow for it otherwise you have to hard tune for the fuel Meaning adjust stoich ratio in the tune and only run that fuel. It's still not that hard to do if you have a Laptop. I know some of the older GM cars( F bodies ) do it that way. If you don't drive it every day it's not really a big deal. Takes all of 5 minutes to figure out what your E content is and flash the correct Stoich value in the tune.

I am just curious why Fluke would assume you lose "Flex fuel" when going to Forced Induction? I think that is what started this confusion. You don't lose anything, but it's a good chance you might have to blend the Ethanol percent down by mixing in more pump gas.

Originally Posted by KingLT1

LT4 only on race gas. Pump gas 850. E85 700. Blend the E down to 50% and you can make close to 800 with the LT4.

Unless you specify what type of fuel you want to run the answers you will receive will be like a lotto machine spitting out numbers.

Originally Posted by KingLT1

No not at all. I have been running a flex fuel sensor with boost since 2019. Depending on fuel system and power level you might have to blend the Ethanol percent down to keep the fuel system happy. E40-60 is really plenty of octane anyway until you get over 1100whp. I run E60 with +30 injectors, LPE HPFP, LT4 tank pump with a JMS. The car makes around 700whp. Stock motor with a blower(10-11psi), fuel system, bolt-ons. Pretty simple combo that will get you around 140mph in the 1/4 mi with a drag pack.

Originally Posted by FlukeSS

You mention you run E60. Is that a tuned E60, or a flex fuel E60?

I'd rather stay away from a tuned E content, would rather stick with flex fuel if possible.

Ultimately do you guestimate how much fuel to mix when filling up, or do you actually measure E content to do the mixture properly.

I want to manually mix fuel as little as possible is why I was asking.

For example I believe right now on my car I run E20-E40 on 1/4 tank of E85, and 3/4 tank of 93. Give or take. at 1/2 and 1/2 I'm at about E40-E60, and full E85 I'm at E80.

[KingLT1]

I know about how many gallons of pump gas and ethanol to pump to hit my target of E60. Then I verify Ethanol content with my torque pro app so I know how much E is in the system. If for some reason I miss and the E is lower, I don't worry about it. If it's over 60%, I'll throw another gallon of pump gas in it. I have only ever had to do that once. I can almost always hit E55-60 every time I fuel up.

[Need4Camaro]

Originally Posted by arpad_m

You I genuinely don't understand his question and it seemed you did, hence mine.

These terms ("tuned" and "flex fuel" E60) make no sense to me... as far as I know, E60 is E60 and this ratio of ethanol to gasoline comes with higher fueling requirement, plus the stoich tables are not populated (they're set to 10% ethanol across the board) by default, so tuning is a necessity no matter what.

So while I know how our cars work for the most part, but thought maybe I missed something and you had extra insight here.

A 'tuned' E60 means a hard set tune, meaning he HAS to run E60 at all times.

A 'flex fuel' E60 uses a flex fuel sensor to provide the ECM signals on how much alcohol content is in the fuel and the ECM adjusts the tune accordingly so you do not detonate when running less E content in your fuel.

Essentially a flex fuel E60 gives you the ability to run E0 all the way to E60 (or in reality E85). You don't 'have' to run E60. A 'tuned' E60 makes it so you HAVE to run E60 at all times.. ..or you risk detonation.. ..this is why it's called 'flex fuel'. It has a 'flexible' fueling table allowing you to run more or less E content and adjusts timing accordingly. You of course lose power the less E content you have, but you maintain engine integrity.