How to run e85 mixtures in your ST!
So I've been running ONLY e30 mix for the last 10k miles or so, with the exception of when I filled up with a tank of 93 to get my final stock turbo tunes done.
When I first started out, I was a little bit worried about how to figure out the correct mixtures needed to hover around the "e30" number--especially if I already had e30 in the tank.
My disclaimer is this: YOU NEED TO BUY A TEST TUBE AND TEST YOUR ETHANOL! Well, sort of. If your e85 station is consistent and frequently busy, you should be okay "assuming" a number AS LONG AS YOU ARE TUNED FOR THAT NUMBER AND KEEP YOUR IN. While you may not come out to exactly e30, as long as you are tuned for it it's mostly okay. I tested my local e85 station and found it was close enough to e85 to take for granted. The kit is less than $20 and can be purchased at Summit Racing: LINK
There are going to be 2 situations for people looking to fill up with e85:
1. You have no e85 in your tank (minus the 10% ethanol in most pump gas)
2. The gas that is left in your tank is already e30 or whatever your desired mix is.
If you're in situation #1, it's very simple. Just wait until you need to refuel, put about 3.3-3.4 gallons of e85 in the tank, then remove the nozzle and fill it up with 93 octane until it clicks. (or test the fuel, and then plug the numbers into the app to determine how much of each fuel you need to put in. This will be covered below)
If situation 2 describes you, it isn't quite so simple. You COULD theoretically pull the same trick, and just add 3.3-4 gallons to your tank and then top it off with 93, but you'd end up with a mix higher than e30, and this effect grows the further from empty your tank is. "Close enough for government work"
I typically run my tank down to the bottom because I'm lazy:
Now here's where the fun part comes in. I use an app that is no longer on the app-store, so for this tutorial I switched to a different app. The app I used can be seen here:
When you get the app, don't be freaked out. You'll see a screen that looks like this, but not everything needs to be filled out. I highlighted the important boxes with red.
Okay. Here is a description of each box:
Desired Ethanol: This is the ethanol "number" you want to reach. If you want e30, put 30 in this box.
Tank Capacity: This is the amount of gas that will fit in your tank. Use 12.4.
% Filled: This is how much gas is left in your tank, as a percentage. What many people don't know is that the Accessport can tell you this, and it's surprisingly very accurate:
The monitor, as you can see, is called Fuel Level Input. Mine ranged from 0.0 to 31.3 on my way to the gas station, and the number is VERY sensitive to the car being on an incline. Try to check this when you're on level ground. My gas station isn't 100% flat, so I do it before I pull up to the pump. I also prefer to check this while the car is off, but in accessory mode.You will have to manually turn on the AP if you do this using the button. Put this number into your app, EG 17.6 in my case.
% Ethanol in tank: I run an E30 mix, so I need to put 30 here.
Gas: % Ethanol: Gas typically has up to 10% ethanol, so put 10 here.
Ethanol: % Ethanol: Either put 85 here, or test your e85 and put the true number.
When you put these numbers, you will see the following:
As you can see, it tells you exactly how much of each fuel to put into your vehicle. PUT THE E85 IN FIRST! This assures that if something goes wrong, you put too much ethanol in the tank vs too much 93 octane. It's better to overshoot than to undershoot.
Here we go!
I was a little too slow stopping the pump, but again, better too have too much e85 in the tank than not enough.
Time for 93. Put the pump in and fill it till it stops.
Aaaand there we go! Your tank is full and has the correct E mixture in it.
My main purpose for this thread is to show people the Fuel Level monitor on the Accessport.
There are 2 improvements for this little guide:
You could (and should) test your fuel for its ethanol percentage. This will make your calculations more accurate and SHOULD BE DONE. HOWEVER, if you don't do it, it's not the end of the world. I tested my old gas station (10 min down the road) and it had around 82% ethanol. I have not tested this new station but I've been using it for many months now, and it was the fuel my car was dyno tuned on.
The other improvement? Just buy an ethanol content gauge and then you don't need to do this by hand.
I'm going to edit this post tomorrow morning, when I'm not tired out of my mind. Excuse me if it currently seems a bit ranty--I took a few benadryl an hour or so ago.
Thanks all! Corn is the bomb and more people should run it.
So I've been running ONLY e30 mix for the last 10k miles or so, with the exception of when I filled up with a tank of 93 to get my final stock turbo tunes done.
When I first started out, I was a little bit worried about how to figure out the correct mixtures needed to hover around the "e30" number--especially if I already had e30 in the tank.
My disclaimer is this: YOU NEED TO BUY A TEST TUBE AND TEST YOUR ETHANOL! Well, sort of. If your e85 station is consistent and frequently busy, you should be okay "assuming" a number AS LONG AS YOU ARE TUNED FOR THAT NUMBER AND KEEP YOUR IN. While you may not come out to exactly e30, as long as you are tuned for it it's mostly okay. I tested my local e85 station and found it was close enough to e85 to take for granted. The kit is less than $20 and can be purchased at Summit Racing: LINK
There are going to be 2 situations for people looking to fill up with e85:
1. You have no e85 in your tank (minus the 10% ethanol in most pump gas)
2. The gas that is left in your tank is already e30 or whatever your desired mix is.
If you're in situation #1, it's very simple. Just wait until you need to refuel, put about 3.3-3.4 gallons of e85 in the tank, then remove the nozzle and fill it up with 93 octane until it clicks. (or test the fuel, and then plug the numbers into the app to determine how much of each fuel you need to put in. This will be covered below)
If situation 2 describes you, it isn't quite so simple. You COULD theoretically pull the same trick, and just add 3.3-4 gallons to your tank and then top it off with 93, but you'd end up with a mix higher than e30, and this effect grows the further from empty your tank is. "Close enough for government work"
I typically run my tank down to the bottom because I'm lazy:
Now here's where the fun part comes in. I use an app that is no longer on the app-store, so for this tutorial I switched to a different app. The app I used can be seen here:
When you get the app, don't be freaked out. You'll see a screen that looks like this, but not everything needs to be filled out. I highlighted the important boxes with red.
Okay. Here is a description of each box:
Desired Ethanol: This is the ethanol "number" you want to reach. If you want e30, put 30 in this box.
Tank Capacity: This is the amount of gas that will fit in your tank. Use 12.4.
% Filled: This is how much gas is left in your tank, as a percentage. What many people don't know is that the Accessport can tell you this, and it's surprisingly very accurate:
The monitor, as you can see, is called Fuel Level Input. Mine ranged from 0.0 to 31.3 on my way to the gas station, and the number is VERY sensitive to the car being on an incline. Try to check this when you're on level ground. My gas station isn't 100% flat, so I do it before I pull up to the pump. I also prefer to check this while the car is off, but in accessory mode.You will have to manually turn on the AP if you do this using the button. Put this number into your app, EG 17.6 in my case.
% Ethanol in tank: I run an E30 mix, so I need to put 30 here.
Gas: % Ethanol: Gas typically has up to 10% ethanol, so put 10 here.
Ethanol: % Ethanol: Either put 85 here, or test your e85 and put the true number.
When you put these numbers, you will see the following:
As you can see, it tells you exactly how much of each fuel to put into your vehicle. PUT THE E85 IN FIRST! This assures that if something goes wrong, you put too much ethanol in the tank vs too much 93 octane. It's better to overshoot than to undershoot.
Here we go!
I was a little too slow stopping the pump, but again, better too have too much e85 in the tank than not enough.
Time for 93. Put the pump in and fill it till it stops.
Aaaand there we go! Your tank is full and has the correct E mixture in it.
My main purpose for this thread is to show people the Fuel Level monitor on the Accessport.
There are 2 improvements for this little guide:
You could (and should) test your fuel for its ethanol percentage. This will make your calculations more accurate and SHOULD BE DONE. HOWEVER, if you don't do it, it's not the end of the world. I tested my old gas station (10 min down the road) and it had around 82% ethanol. I have not tested this new station but I've been using it for many months now, and it was the fuel my car was dyno tuned on.
The other improvement? Just buy an ethanol content gauge and then you don't need to do this by hand.
I'm going to edit this post tomorrow morning, when I'm not tired out of my mind. Excuse me if it currently seems a bit ranty--I took a few benadryl an hour or so ago.
Thanks all! Corn is the bomb and more people should run it.
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