E85 Experiment's

[CAV3MAN227]

-So for some reason lately, I've been wanting to experiment with E85. So far, on a full tank of 91 gas, I've put in one gallon of E85 and turned the boost to 15psi. So far no issues, wideband is reading in the low 11's.
-I got to thinking more and the owner's manual shed some more light on this. In the book it states, "Never use fuel containing more than 10% ethanol (ethyl or grain alcohol)." So with doing some basic math, our cars have a 15.9 gallon tank and 10% of that is 1.59. So in theory, we should be able to run 1 1/2 gallons of E85 on a full tank of gas with no side effects.
-A friend of mine with a 92 tleg did a simple fuel test to see where the gas would start to run out. What he came up with was, car started to sputter going up a slight incline, with the needle pointing at the 'E'. When he filled up, he put in 14.1 gallons of fuel. Now that can vary obviously, but that's damn close to being empty. What was weird about that though was, the book says the low gas light should come on at 2.4 gallons or less and his never came on. (I've seen mine once in the past for a split second cause I was on an incline. Never saw it again.) Anyway...
-So something else came into mind, if I was to put in 440 to 550-565cc injectors and run 91 and up octane, I know it would be very rich, car probably wouldn't run at all. But, if you put in enough E85 to lean out the 91, wouldn't you be able to get away with it? To the point of the injectors not going static? I know you don't get the timing advantage but still...
-Any thoughts? Advise? etc. Just seeing what are some cheaper options for a little more power than going piggy-back, full standalone etc.

-Joe

[Alphius]

Injectors would go static at the same time based on measured airflow. Doesn't matter what fuel you have or what size injectors you use. If you don't change the ECU programming it's going to go static at the same airflow.
That being said, for the same power you need much more fuel on E85. So bigger injectors would be a good step, and might even run without ECU reprogramming. However, you need to remember that it'll make the exact same power, and get much worse gas mileage. No benefit.

Lots of gas even if it's not marked on the pump is already between E0-E10. So you cannot mathematically calculate the total Ethanol content that easily. Added to that, E85's actual Ethanol content varies around 85%. It's not exactly E85. It can be down to E70 at some times of the year.

Where the needle points/gas light comes on really is different from car to car. My low light comes on with an eighth of a tank left and takes 14.2 gallons with the needle slightly below the E on the gauge. Mine sputters around hard right hand corners at about 14.8 gallons used.

[CAV3MAN227]

Lots of gas even if it's not marked on the pump is already between E0-E10. So you cannot mathematically calculate the total Ethanol content that easily. Added to that, E85's actual Ethanol content varies around 85%. It's not exactly E85. It can be down to E70 at some times of the year.

-I know the stock ecu wont advance the timing enough to get the best use outta the E85, but if this cant be mathematically calculated and what you are saying is true, you can mix as much as you want, technically, as long as the injectors don't go static, you know what you are doing and your car runs correctly... What I mean is, back in the day when I knew nothing and first got this car, the previous owner told me he was running a mix, 4-5 gallons E85 and the rest 91. The only thing the car had, at that time (xmas 2009) was, an apexi avcr electronic boost controller, so there was no way of telling what the car was doing. Obviously, it didn't hurt the car, cause it still runs to this day and I've taken it on 1300, give or take, mile road trips. Never have had a fuel related issue... yet (knock on wood). So I take it as, if your going to stay with the stock ecu, you can run a mix as long as you have a wideband so you can watch your afr's and you don't lean out. Speaking of widebands, what is the safe range? I've been told 10.8 - 11.2, I've also heard 12.5 is even ok at wot. I'd like to know more of a clarification on that.

-So far with testing, I've up'ed my boost to 15psi in 5th gear (with 4.11's), with wide open throttle, I've seen low 11's, with occasional hits in the high 10's (afr's). Again, this is with one gallon E85 with the rest 91 octane. With so little E85, at this point, I don't think it has any affect or making any difference.

-How would you know when the injectors would go static? Check engine light, rich fuel smell, etc? Obviously its not worth putting in bigger injectors and running more E85 without any gains, esp. when the fuel isn't available like unleaded gas is. Also, what about running higher octane gas? I know its more expensive, but is it better gains than an E85 route?

-Joe

[kimokalihi]

I ran out of fuel on the freeway and my fuel light only came on for a minute and then went off again before it started chugging. I put only about 13.5 gallons in it to fill it after that.

[macipusy]

You can probably go as high as 30% ethanol and still be OK AFR wise...that is where mine started to lean out when I was running my experiments.

You will actually make less power on E85 if you don't advance the timing and leave boost constant...higher octane burns slower, so you need the extra degrees of crank rotation to utilize the full burn.

Joe...you are at the point in your build where you need to think about good EM. Big power gains are to be had from tuning.

[Alphius]

Sure, you can run a mix if you want. You're not going to see any gains though. You will get worse gas mileage and slightly less power. You need to tune to take advantage of the knock resistance of the ethanol.

There's no reason you couldn't run 15psi on straight 91/92 octane gas either. The ethanol isn't helping you at all at that level.

As far as AFR, and to keep it safe on a turbo car, try to stay richer than 11.5:1. 12:1 is about the limit of safety on gasoline in a turbo car.

[CAV3MAN227]

Joe...you are at the point in your build where you need to think about good EM. Big power gains are to be had from tuning.

-Yea I know. Standalone is a big price step so I'm just exploring my options where I'm at.

higher octane burns slower, so you need the extra degrees of crank rotation to utilize the full burn.

-So are you saying, without tuning, that even running higher octane fuel, above 92, you wouldn't benefit either?

As far as AFR, and to keep it safe on a turbo car, try to stay richer than 11.5:1. 12:1 is about the limit of safety on gasoline in a turbo car.

-Well this is good to know. Did some more testing last night and saw 11.2's and 11.4's @ 15psi in 5th gear, WOT.

-So based on the comments here already, seems like E85 is pretty much out of the question on a stock ecu. The only possible gain I can see from it now and this really depends is, could be cheaper to fill up your tank. But that would take a calculation from E85 price to 91 prices to what your fuel mileage is to what your burning, etc, to see if its even cost effective. <--- Maybe an experiment for another time.

-Joe

[macipusy]

The only reason I ever mixed E85 in with 91 octane is for safety. My Tleg would sometimes detonate on 91 octane and mixing in 3-4 gallons E85 always eliminated it. Now I don't ever run 91 unless I have to for a road trip lacking in E85 stations.

[Dave_J]

To get the advantage of E-85 you need to up the compression ratio to about 12.5:1 for a NA and 10 on a turbo engine. Just bumping the ignition timing will not give you much if any ay all.

We have a 67 Dart with a (1980) 318 that was built for E-85. It has 12.5:1 compression, Ported Magnumn RT alumumn heads, 276 degree Lunati Voodoo cam and headders. Make 425 HP. It requires a HIGH torque starter to crank and its slow at that. Gets 18 MPG.

[Legacy777]

I'll throw my 2 cents into the mix.

Regarding the ethanol compatibility. The main reason manufactures had notices not to run above E10 blends was due to ethanol material compatibility. At the E10 level, the behaivor is the same as straight gasoline on metals and elastomers (rubber hoses, o-rings, etc). Above that level certain materials can have adverse affects by the ethanol. In carbon steel, ethanol can cause stress corrosion cracking (SCC). In certain elastomers, (certain buna-n seals) it can cause swelling of rubber, and ultimately deteriorate it.

The pipeline industry has been very interested in ethanol because it's not primarily transported by pipelines. The main reason being the SCC risk associated with carbon steel pipelines. There is only one pipeline company that I know of that is transporting it in their pipeline. I've been involved with some of the industry research that's been on-going since about 2007 or so. It's been educational and interesting seeing multiple sides of the story, (ethanal producers, transportation companies, auto manufacturers, & end users).

If you really want to get into an ethanol build, this ethanol content meter would be a good thing to have.

http://www.zeitronix.com/Products/ECA/ECA.shtml


As others have pointed out, unless you are having detonation issues, the added octane from the ethanol or (higher octane gasoline) won't really help you make any more power. It may provide a safer margin for where you're running the engine currently, or allow you to run more boost. Tuning is really where you make the power. You can accomodate a much more narrow set of circumstances for your particular engine compared to the factory's broad tune.

For AFR's, I like to see around 11 to 1. 12 to 1 is where you can make "max" power, but it's very close to the ragged edge and not very safe to be. The stock ECU's tend to run rather rich since they did not come with intercoolers.

[CAV3MAN227]

-Thanks for all the replies guys.

-How much E85 is acceptable if you were having detonation issues? I know macipusy said up to 30% before it starts leaning out, but, one gallon, two gallons? Like I said before I've been doing my tests on one gallon with no know side effects and based on the information given already, I shouldn't expect to.

-Also, where is the signal coming from with the low level fuel light and would you still have it if swapped to a walbro or aftermarket fuel pump?

-Joe

[Alphius]

Up to 10% is acceptable and has no effect on fuel system components (according to research). Any more than that can cause accelerated wear of fuel lines, rubber seals, fuel rails, injector internals, fuel pump internals, etc. To be fair, most relatively modern cars have ethanol resistant fuel systems, but you are taking a chance running any ethanol. Plenty of people have gone years running ethanol and had no bad side effects but you need to evaluate whether that is worth it for you to try or not.

I have a Walbro and still have the low fuel light. It is triggered in the same way that your fuel gauge measures fuel. Won't be affected by a pump change.

[cj91legss]

I'm trying to figure out how you guys are getting more then 11 gallons in your tanks..... On E i have NEVER seen more than 12 gallons put in...

[macipusy]

I have gotten 15.1 gallons in my Tleg at one point, when I ran it with the gas light on for a while.

[CAV3MAN227]

-I'm about to figure out what my fill-up will be here real soon.

-Joe

[Alphius]

I'm trying to figure out how you guys are getting more then 11 gallons in your tanks..... On E i have NEVER seen more than 12 gallons put in...

That just means you have lots of spare gas when it says E.

If I fill up around 11-12 gallons used my gauge is still at about an eighth of a tank.

[cj91legss]

I'm all sketchy about being on E haha...

[Legacy777]

See the little round silver thing on the fuel sender in this pic?

http://www.main.experiencetherave.com/s ... P_6723.JPG

That's the low fuel light sender. When fuel drops below that, the light will come on.

As for driving on E, just get a gas can to carry in the car and drive around so when you run out you can refill the tank.

[cj91legss]

Hmm, I'm gonna go modify mine so it doesn't sit in the tank so low

[Legacy777]

You can move the entire sender up and down on the fuel pump bracket.

[Ubermeister]

I have been running E85 for six months now. I blew a headgasket now (cheap ebay headgasket) I now found some black tar-like residue in the inlets on the heads. Is this maybe from the o-rings in the injectors. (old o-rings from maybe -96) I will post pictures when i get a chance. Also, i found light rust on the cylinder walls.

[Legacy777]

Yeah, if you can post some pictures, that would help.

Ethanol is a very good solvent, so it's not likely going to leave a residue, but without seeing it, it's a little difficult to say for sure.

[Ubermeister]

Hope my pictures work. The residue reminds me of that brown permatex. If its oil, it still cannot be wiped away without any solvent..

Tried another picturelink.

[CAV3MAN227]

^No working pic.

-Joe

[Ubermeister]

I found another guy here in Sweden with the same issue..

I think it might be oil from the turbo, but why it would get so dry, i have no idea..

"Edit" : I found that the fuel-companies in Sweden adds a colouring-agent to the E85, and this may cause the fuel to leave a residue..