Proper Procedure for using E based maps

[Shelby Miles]

I'm curious as to what the general consensus around using E maps with an E analyzer like Fuel It.

a. Do you add E and watch the analyzer get to the desired mix and then flash the E map to support it?

or

b. Flash the E map, add E with a rough estimate using what 93 is in the tank, watch the E gauge for desired level while taking it really easy. Once the E level matches the tune, give it the beans?

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[razorlab]

I'm curious as to what the general consensus around using E maps with an E analyzer like Fuel It.

a. Do you add E and watch the analyzer get to the desired mix and then flash the E map to support it?

or

b. Flash the E map, add E with a rough estimate using what 93 is in the tank, watch the E gauge for desired level while taking it really easy. Once the E level matches the tune, give it the beans?

Don't use the Fuel It, use an ethanol kit that has a CAN connection, then use BM3 or Ecutek flexfuel and not worry about any of those questions.

 

[Thraxbert]

There are two ways to tune the car:

1) For a specific ethanol content. The car must always have that ethanol percentage (or slightly higher), and never lower. You must know what ethanol percentage is coming from the pump. You use a phone app to calculate the right mix of e85/93oct against what is in the tank to hit that percentage. This is primitive.

2) You specifically install a flex fuel kit, which enables the tune to adjust engine parameters based on the ethanol percentage in the tank. It's flexible because you can switch between 93 octane, full 85% ethanol, or any ethanol percentage in between. If you are on the car's OEM fuel system, you will still need to do some calculations to make sure the fuel is no more than 60% ethanol content. But if the car is anywhere between 10% and 60%, it'll be fine.

You want the second one, and you want to install a kit that is specifically listed as "flex fuel" to enable this. There are many options on the market for the Supra. You'll still need to use a phone app to rough in the 60% number for peak performance, but you don't have to be very precise about it. Or if you just want to be lazy and pump a full tank of 93, you can do that.

And just because I need to get this out of my system, which is directed to the universe and not any one person in this thread:

ETHANOL/E85 IS NOT FLEX FUEL. It's only "flex fuel" when the car can automatically adjust to any ethanol percentage in the gas tank. Otherwise it's just "ethanol mix" tune for a specific percentage.

//edit:

For example, let's say I'm trying to target E30 specifically.

1. I know that 93 octane gas is always 10% ethanol.
2. I know the e85 from my local gas pump is real 85% ethanol, because I've tested it.
3. I know that my gas tank is 13.7 gallons.
4. I know that I have 25% tank left, because the car tells me I do over OBD.
5. I know that 25% tank is full 93, which means it's 10% ethanol.
6. To reach 30% ethanol content, I need to pump 3.65 gallons of e85 and 6.62 gallons of 93 octane.

 

[Shelby Miles]

Don't use the Fuel It, use an ethanol kit that has a CAN connection, then use BM3 or Ecutek flexfuel and not have worry about any of those questions.

I'm using the MHD that does have the CAN connection. I'm also using MHD for the tuning which they haven't released their flex-fuel option yet. So, in the meantime, I would like to try out an E30 OTS map but do so safely.

 

[Shelby Miles]

There are two ways to tune the car:

1) For a specific ethanol content. The car must always have that ethanol percentage (or slightly higher), and never lower. You must know what ethanol percentage is coming from the pump. You use a phone app to calculate the right mix of e85/93oct against what is in the tank to hit that percentage. This is primitive.

2) You specifically install a flex fuel kit, which enables the tune to adjust engine parameters based on the ethanol percentage in the tank. It's flexible because you can switch between 93 octane, full 85% ethanol, or any ethanol percentage in between. If you are on the car's OEM fuel system, you will still need to do some calculations to make sure the fuel is no more than 60% ethanol content. But if the car is anywhere between 10% and 60%, it'll be fine.

You want the second one, and you want to install a kit that is specifically listed as "flex fuel" to enable this. There are many options on the market for the Supra. You'll still need to use a phone app to rough in the 60% number for peak performance, but you don't have to be very precise about it. Or if you just want to be lazy and pump a full tank of 93, you can do that.

And just because I need to get this out of my system, which is directed to the universe and not any one person in this thread:

ETHANOL/E85 IS NOT FLEX FUEL. It's only "flex fuel" when the car can automatically adjust to any ethanol percentage in the gas tank. Otherwise it's just "ethanol mix" tune for a specific percentage.

If MHD doesn't deliver MHD+ before the end of Jan, I will be switching to ecutek to get flex-fuel.

 

[SoDakMk5]

There are two ways to tune the car:

1) For a specific ethanol content. The car must always have that ethanol percentage (or slightly higher), and never lower. You must know what ethanol percentage is coming from the pump. You use a phone app to calculate the right mix of e85/93oct against what is in the tank to hit that percentage. This is primitive.

2) You specifically install a flex fuel kit, which enables the tune to adjust engine parameters based on the ethanol percentage in the tank. It's flexible because you can switch between 93 octane, full 85% ethanol, or any ethanol percentage in between. If you are on the car's OEM fuel system, you will still need to do some calculations to make sure the fuel is no more than 60% ethanol content. But if the car is anywhere between 10% and 60%, it'll be fine.

You want the second one, and you want to install a kit that is specifically listed as "flex fuel" to enable this. There are many options on the market for the Supra. You'll still need to use a phone app to rough in the 60% number for peak performance, but you don't have to be very precise about it. Or if you just want to be lazy and pump a full tank of 93, you can do that.

And just because I need to get this out of my system, which is directed to the universe and not any one person in this thread:

ETHANOL/E85 IS NOT FLEX FUEL. It's only "flex fuel" when the car can automatically adjust to any ethanol percentage in the gas tank. Otherwise it's just "ethanol mix" tune for a specific percentage.

//edit:

For example, let's say I'm trying to target E30 specifically.

1. I know that 93 octane gas is always 10% ethanol.
2. I know the e85 from my local gas pump is real 85% ethanol, because I've tested it.
3. I know that my gas tank is 13.7 gallons.
4. I know that I have 25% tank left, because the car tells me I do over OBD.
5. I know that 25% tank is full 93, which means it's 10% ethanol.
6. To reach 30% ethanol content, I need to pump 3.65 gallons of e85 and 6.62 gallons of 93 octane.

This is the same app I use. I pair this with the factory Supra app to tell me how many gallons I have left

 

[Shelby Miles]

There are two ways to tune the car:

1) For a specific ethanol content. The car must always have that ethanol percentage (or slightly higher), and never lower. You must know what ethanol percentage is coming from the pump. You use a phone app to calculate the right mix of e85/93oct against what is in the tank to hit that percentage. This is primitive.

2) You specifically install a flex fuel kit, which enables the tune to adjust engine parameters based on the ethanol percentage in the tank. It's flexible because you can switch between 93 octane, full 85% ethanol, or any ethanol percentage in between. If you are on the car's OEM fuel system, you will still need to do some calculations to make sure the fuel is no more than 60% ethanol content. But if the car is anywhere between 10% and 60%, it'll be fine.

You want the second one, and you want to install a kit that is specifically listed as "flex fuel" to enable this. There are many options on the market for the Supra. You'll still need to use a phone app to rough in the 60% number for peak performance, but you don't have to be very precise about it. Or if you just want to be lazy and pump a full tank of 93, you can do that.

And just because I need to get this out of my system, which is directed to the universe and not any one person in this thread:

ETHANOL/E85 IS NOT FLEX FUEL. It's only "flex fuel" when the car can automatically adjust to any ethanol percentage in the gas tank. Otherwise it's just "ethanol mix" tune for a specific percentage.

//edit:

For example, let's say I'm trying to target E30 specifically.

1. I know that 93 octane gas is always 10% ethanol.
2. I know the e85 from my local gas pump is real 85% ethanol, because I've tested it.
3. I know that my gas tank is 13.7 gallons.
4. I know that I have 25% tank left, because the car tells me I do over OBD.
5. I know that 25% tank is full 93, which means it's 10% ethanol.
6. To reach 30% ethanol content, I need to pump 3.65 gallons of e85 and 6.62 gallons of 93 octane.

Thank you the detailed answer.

 

[AndyK5]

There are two ways to tune the car:

1) For a specific ethanol content. The car must always have that ethanol percentage (or slightly higher), and never lower. You must know what ethanol percentage is coming from the pump. You use a phone app to calculate the right mix of e85/93oct against what is in the tank to hit that percentage. This is primitive.

2) You specifically install a flex fuel kit, which enables the tune to adjust engine parameters based on the ethanol percentage in the tank. It's flexible because you can switch between 93 octane, full 85% ethanol, or any ethanol percentage in between. If you are on the car's OEM fuel system, you will still need to do some calculations to make sure the fuel is no more than 60% ethanol content. But if the car is anywhere between 10% and 60%, it'll be fine.

You want the second one, and you want to install a kit that is specifically listed as "flex fuel" to enable this. There are many options on the market for the Supra. You'll still need to use a phone app to rough in the 60% number for peak performance, but you don't have to be very precise about it. Or if you just want to be lazy and pump a full tank of 93, you can do that.

And just because I need to get this out of my system, which is directed to the universe and not any one person in this thread:

ETHANOL/E85 IS NOT FLEX FUEL. It's only "flex fuel" when the car can automatically adjust to any ethanol percentage in the gas tank. Otherwise it's just "ethanol mix" tune for a specific percentage.

//edit:

For example, let's say I'm trying to target E30 specifically.

1. I know that 93 octane gas is always 10% ethanol.
2. I know the e85 from my local gas pump is real 85% ethanol, because I've tested it.
3. I know that my gas tank is 13.7 gallons.
4. I know that I have 25% tank left, because the car tells me I do over OBD.
5. I know that 25% tank is full 93, which means it's 10% ethanol.
6. To reach 30% ethanol content, I need to pump 3.65 gallons of e85 and 6.62 gallons of 93 octane.

What if by mistake you fill up on E85 completely and on the stock fuel system? Can you just drive it slowly at low rev range where injectors are not maxed out until there is enough room in the tank to add in fuel?


How does the calculations differ for 91 octane mix? Is it just the final mix is lower in octane rating than doing it with 93? I mean E50 is gonna be high enough in octane so I am not sure if 93 is bringing more to the table.


On a more extreme scenario, what happens if you mix 87 octane regular gas in to E50 lets say. Is that a worse mix than 93 mixed to e50? They both should be the same amount of ethanol vs gas I think.

 

[Thraxbert]

1) yes

2) Emix tunes are always based around the octane of your starting gasoline ("scaling the tune"). The final ethanol percentage is the same, but the total Anti-Knock Index (octane) will be lower than a mix and tune that starts with 93.

3) Same. Total AKI of the mix is lower. Lower AKI means less boost. You could add even more ethanol to get the AKI back. E50 starting with 87 is about 97ish octane (AKI), whereas it's 100ish with the 93 as a starter. To get 100ish out of 87 as a starter, you'd have to pump E65.

A few points of octane may not seem like much, but on my boosted 3.8L V6, it's typical to run E30 (96 octane). That's only three points above 93 gas, but I can put 4 extra pounds of boost into the car, which is an extra 100WHP.

 

[Avarela99]

I have a customer E50 map on MHD and use a fuel it sensor to help make sure I’m running the proper percentage of ethanol haven’t had an issues with fuel it. I agree that having a true flex fuel tune is easier than switching maps and measuring mixtures but as long as you are watching the percentage, running proper fuel, and are cognizant of your E blend you will be fine.

 

[i3igpete]

3) Same. Total AKI of the mix is lower. Lower AKI means less boost. You could add even more ethanol to get the AKI back. E50 starting with 87 is about 97ish octane (AKI), whereas it's 100ish with the 93 as a starter. To get 100ish out of 87 as a starter, you'd have to pump E65.

the mobils in my area list octane for each eblend, so it seems like they are using 93 as the base fuel. Of course, a gas station owner with a label maker probably isn't the most trustworthy source.

 

[Thraxbert]

If they care enough to give you estimated octane with a label maker, I'd say the station operator knows what's up and does indeed blend with 93. It's so unusual and specific I'd give benefit of the doubt.

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