I've done some research on E85 and seen alot of good feedback from the guys that use it but the only thing is all the comparisons I found were to pump 93. My question is what are the advantages of E85 over 110 racegas besides the price. I have two local stations that sell E85 for around $1.6X and my 110 costs me $6.75. Would I be better to take up E85 and save me some money or stay with 110. It's a drag car only so I'm not worried about the added fuel consumption so much. I'll throw in a few other options to pick from too.

 

Stoich for E85 is like 9something:1 as opposed to 14.7:1 for gasoline. You'd need to retune your fueling accordingly. Also ethanol is corrosive to metal parts and rubber hoses. E85 has an octane rating of around 100 to 110.

 

I'm a ways from starting to tune so thats not an issue and have yet to buy any of my fuel components.

 

I'd like to run E85 too, I just want more information of how to deal with the corrosive element.

 

So would I and any other information that can be provided. I'm just trying to justify that it's that much better than 110 for the cost.

 

For $2/gal instead of what, $8/gal? I would definitely choose it lol. If it's just a drag car I guess it doesn't matter too much.

 

Thats a budget determinded by how many hours I get per week unfortunatly I only work part time with school and they cut all the part times down to around 15 hours a week.....

 

turbomustangs.com you can read up on e85, also ls1tech has some good threads. I personally watched my friends dsm make 780hp to all 4 wheels on e85 a few weeks ago, I don't it has any less potential than 110 at all. Also e85 will allow more timing to be ran on the same boost level vs pump gas, plus it burns cooler, AND will make a turbo spool faster.

Pump/meth I wouldn't even consider an option if it's a drag only car.

If you can afford the bigger fuel system, no reason not to do e85 vs 110 on your setup. What kind of power are you looking to push?

As far as being corrosive, do some research, a lot of the corrosive stuff is just myths from when people first started using it.

 

Remeber one thing when switching to E85. You will have to add more fuel to get it to burn the same, about 10:1 or so. But when you read your O2 feedback, it still reads the oxygen in the exhaust stream. This means that will still want to obtain a reading of 12.5:1 at WOT and 14.7:1 at cruise from your Wideband O2 sensor.

Think of it this way, the O2 sensor measures unburned oxygen in the exhaust, so you want to add enough fuel to keep the unburned oxygen the same. And therefore keep the same O2 reading from the sensor.


This is the same stuff that LC_Vette got his 900rwhp pull on his 355ci LT1 @ ~22psi.

 

My goal is 950+ plus at the wheels but I would be more than happy with way less(around 850).

 

No need to 12,5 on E85, 11,5-12 works great.

 

Are you saying that the o2 sensors will still read 450mV (14.7:1), even when you've achieved a stoichiometric mixture of ~10:1 with E85?

 

You have to think of it in terms of the elements, break it way down. If I put in a hydro carbon and oxygen and explode them I get left over/unburned oxygen, water, CO2, and a bunch of heat. The goal is to get the proper amount of left over oxygen. That's why we have an oxygen sensor(or that was the easiest to invent). This is what we use to make sure that the ratio is correct.

So for gas its basically C8H18 + O2 => C02 + H20 + O2
With ethanol it is C2H6O + O2 => CO2 + H20 + O2

Balance the equations out C8H18 + 13 O2 => 8 CO2 + 9 H2O + 0.5 O2
C2H6O + 4 O2 => 2 CO2 + 3 H2O + O2

Obviously these equations are simplified. And let’s not forget that gas and e85 are mixtures and this equation is not by any means exactly representative, but the basic idea and concepts are there.

So the less fuel you have, the more left over O2 is in the exhaust stream, which is what the Oxygen sensor measures. If you have an abundant amount of left over oxygen in your exhaust, 20:1 air/fuel ratio, then you add more fuel to bring it back into line with what it should be(14:1).

Now with ethanol you need to run close to a 10:1 ratio, but as you can see from the formulas above the are alot less C's and H's to produce as much CO2 and H2O, so you need to add more fuel for the same amount of air as you normally do to have the same amount of left over O2 in the exhaust stream.

Since your oxygen sensor conveys its information by a voltage output, the ECU doesn't know/care what is going on. It uses its pre programmed calculation to turn a voltage into an air/fuel ratio. When you are using something other than gasoline then you need to modify the calculation, but it is easier to just read the stuff read and call it good.

The end goal is to get the correct amount of voltage out of the sensor. This tells you how much unburned O2 is in the exhaust stream and that is what you are trying to regulate.

 

One thing to keep in mind when doing a high boosted FI car and considering E85 just to save some money;

1. Yes, it is corrosive, so to combat this, you'll need to setup your fuel system (hoses, connections, fittings ect.) with parts that will handle running the E85.

2. And this one is a BIG one to keep in mind, E85 is not always mixed the same. Sometimes in the summer it is mixed differently than in the winter. So you'll either need a very conservative tune that your car will be okay on no matter what the mix of E85, or you will constantly need to be tuning on the fly to compensate the different mixes of E85.

3. You may think you are saving a bunch going to E85, but keep in mind that your gas mileage will be much worse with E85, and in the end you probably won't really be saving too much (and some guys I know say they actually end up about the same as putting 93 octane in it).

Here's the way I see it. If you have a high dollar setup, running that kind of power level, you really should just buy race gas. Its expensive, but it will for sure keep you safe 100% of the time, protecting your large investment under the hood.

If thats not really in your budget, I next reccomend doing what I did, and going with meth injection. It will be as reliable as your meth injection pump essentially. If you do the maintenence on it (replacing the pump every so many years), then it will be reliable. If you still need extra insurance that it will work, Snow Performance offers a safe injection system that constantly moniters the meth flow, and if at any time the meth isn't injecting like its supposed to, it will bleed off your boost and keep you safe from detonation.

93+ Meth injection is what most of us on here run. IMO it is most cost effective overall.

 

Well It's only a drag car. It would take a lot of money to turn it back to a street car now. The E85 does change in winter but it doesn't mean anything to me because this is Iowa and by time they change it my race season is over and there is snow on the ground. I should have probably left the 93 + meth out because it's pretty much a step backwards since I already run 110. I will probably just stick with the 110 because it's available at the track and I won't have to go out of the way to get fuel since my budget does allow it.