I was talking to a guy tonight who drives a mazda6. He said he ran e-85 even though though his car wasnt a flex fuel car and that one of the differences was that the e-85 was more corrosive compared to unleaded fuel.

He said I should try running it since it was 105 octane. He puts in some Marvel Mystery Oil or some Lucas Oil product which neutralizes the extra corrosiveness and that it works great. I know our apex seals are carbon which might not work well since it is more corrosive but I don't know enough about all of that science.

At that point I realized I hadn't seen anybody on here mention anything about using E-85 yet.
And me lacking knowledge about some of those things figured I would ask if it would work and if not why not.

It is alot cheaper and with my new setup i'm going to need to start running higher octane which is A) More Expensive B) Harder to find C) Farther away to get, so this would solve part of that problem.


So If anyone has any information or an opinion about this I would like to see/read it.




Note: I am not going to run out blindly and try this. I understand the importance of spending a little more now on better octane then spending alot more down the road on a new engine because I didn't want to spend that little extra. And I did run a number of searches for E85 and nothing came up.

 

Our apex seals are carbon? Why the HELL are people spending $2000 bucks for a set of 6 carbon seals!?!?!?!?


No but seriously, our apex seals are not carbon. And E-85 isn't recommended for your turbo FC, either =P, but you may not have a choiiiiccceeee...

It is higher octane to an extent, and only if you add MUCH more. It takes (correct me if I'm wrong, somebody) 2-3x as much ethanol to equal the same amount of power in gasoline.

That said, 15% ethanol isn't a big deal. Yes, ethanol will eat through your rubber fuel lines, and the rubber linings between the fuel lines and the exhaust , but most likely not with only 15%. Besides, chances are, all of the gas around you (aside from BP) will probably all be E-85 by now anyways, as it is basically mandated now.

 

Sorry about that. I meant to put, I know our seals are different which might not work well since it is more corrosive but I don't know enough about all of that science.
And by different I meant from piston engines in general.

I didn't think it was recommended or even something I would want to try. I was pretty sure someone else would have said something by now if it was. Honestly all I know is that E-85 comes from corn. I knew it have ethanol in it but had no idea about the makeup of it at all. Maybe my first post should have just been, " What's the deal with E-85?"

Sorry for sounding stupid. I haven't taken the time to get caught up with alot of things especially technology wise. I fell out of the loop now. This has been a very stressful last few months. All I do is work and sleep and work on the car.

 

DON'T, at least not without a standalone properly programmed for it. As has been stated you need to use a lot more (much lower stoicheometric ratio), so even though it's cheaper, you'll use a lot more. If you don't do something to cause more fuel to be injected your engine will be taking a long walk down a short plank.

 

actually i did with with my old N/A, and E85 is rediculously expensive. There may be no benifit to running e85 it may give you a slight increase in power. but not by much. Rotary eats up the e85 like a 6L v12 on regular unleaded exon gas. BUT what i did notice where the e85 does make a slight noticable difference is EMISSIONS. tailpipe emissions is 45% lower with e85, I dont know exactly how it works but im gona give it a few more goes on my TII in the next few days. Seeing as how i work at emissions i can use the dyno whenever i feel like it.

 

Our apex seals are made from a metal-carbon alloy. But the problems isnt the apex seals, its more of a problem with the Ethanol be corrosive to Aluminum and Rubber. AND that the alcohol is not dielectric like gasoline. So you need a fuel pump that can handle 1) not being corroded and 2) not flowing the alcohol through the pump to cool it like most traditional gasoline pumps, which expose the alochol to direct electrical contact. You also cant use rubber or aluminum fuel lines.

There are actually several E85 threads floating around here that had some good information. There are even more on google. Basically you have be concern with the construction of the fuel system and your fuel controller. The Stoichiometric ratio of ethanol is close to 9:1 whereas gasoline is about 14:1. Basically, that means you need more ethanol to run your vechile. But there are numerous other little factors to consider, such as, you can run ethanol leaner than gasoline and you can run more timing.

As for this, just ensure that your project uses "alcohol safe" componenets and do your research. There is a ton of information on google that will apply universally.

 

again, they are a carbon-steel alloy. People are spending big bucks on CERAMIC seals. Big difference.

Again, see above. But also, after 1985 basically any vechile sold in the u.s. was engineered accept E10 fuels. Hense the extra nitride coatings on internals. But in stock form, most cars can't accept heavy ethanol fuels. Things have to been done.


ethanol stoich is 9:1, gasoline is 14:1. The amount of fuel doesnt dictate octance, but the amount of fuel will affect the correct running on the engine. So you do need more ethanol to run correctly, but there are numerous advantages of this.

E10 is common and usually not required for you to be notified of when purcheseing. Dont see how anything the exhaust will be affected. E-85 stands for 85% ethanol, 15% gasoline, BTW and is not mandated in any way, shape or form.

 

You can easily get away with this on a megasquirt as well. But generally if you plan on taking full advantage of its higer octance tendancies, then you probably have already considered running some form of fuel controller. You also usually have run a larger injector size.


Just putting E85 into your car and doing nothing else will really only kill your fuel consumption and probably decrease power.

 

wow everyone jumped on my apex seal mistake. haha
Again I'm not actually going to do it and I wasn't even really serious about thinking about it. I was just wondering if it was an option. Thanks for all the information guys.

 

the worst part is you would need different seals and fuel pump (it eats the coating off the windings so the pump shorts out) to stand up to it and i doubt the mystery oil or lucas (which i do love) would make a difference so all new seals that would have to be custom and crap... though if you found a race rx7 that ran off alcohol and did a similar seal and hose set up it might work?

 

i was contemplating on running my tii on e85 for a while but there are several issues with doing this. You need a boat load more fuel when running e85. i believe it is about 1.5 times that you would need if you were running petrol. also, ethanol is corrosive thus you need to change a few things. the hardline from the tank is ok; however, the rubber lines need to be replaced wiht something that can deal with the alcohol. You must modify your rails to accept you new fuel lines. This is assuming that you can not find fuel line that is alcohol resistant, i havent really looked into this b/c my project wouldnt allow it. You can not use most aftermarket fuel rails because they are aluminum. Now to the injectors. You have a few options here. first is to take your stock injectors and get them outfitted wiht flex fuel orings. marren fuel injection has these. this should be ok for relatively stock configurations. the second option is for people trying to make some serious power. You are quickly going to realize that you need a crapload more injector. For my application, whihc was to get 500 to the wheels, i needed fuel for 600 flywheel hp. using marrens calculator with the bsfc=1.4 i would need 11,025 cc/min of fuel. This is problematic at best. To make things streetable you cant run 1680cc/min primaries, so lets say we run 1000cc/min, are still left wiht 9000 cc/min of injector we need. so using 1680cc/min injectors we would need 5.3 of them so round to 6 1680 injectors. So now you got to figure out where the hell to put these. Also, you need to make sure you buy flex fuel injectors. So now we have our 8 injectors, you need some sort of ecu to control things. Also we need to get a couple of fuel pumps to get us eneough fuel and an alcohol safe fpr. Also, i have seen quite a few people use walbro pump with e85. Walbro does not rate them for flex fuel but they people have used them successfully. I believe sx and aeromotive make pumps. You could always go get a pump out of a flex fuel vehicle. Needless to say you are going to have multiple pumps to get that much fuel. Now your gas tank maybe an issue as well. I did a bit of research on this and evidentally there is some coating they used to use on the inside of gas tanks that is easily corroded by the alcohol, it was not clear if our cars had this but just to be safe, toss in a new fuel cell. plus, it would be nice to have sumps for the pumps and some added fuel capacity because you can quickly drain a tank if you are using as much fuel as this would. In the end i decided against doing this for a few reasons. The main reason was that there was only 1 e85 station near me. i want to be able to drive where ever i please and still be able to get gas. secondly i frankly didnt feel like spending 1200 on pumps, 1000 on a fuel cell, 1200 on injectors, 500 on fuel lines, alot on a manifold. you get the picture. A note onthe injectors, i realized that motec makes a 260lb injector, so running 2 of those and 2 1680s on the secondaries would be eneough fuel. it would make mounting the injectors easier becuase there woudl be 2 less. Grant it, that this would be expensive to do, but it does have a few advantages. 1. ethanol has a high octane rating 2. ethanol cools the intake charge more than gasoline when it vaporizes. im not entirely sure but you may be able to do with out an intercooler with this 3. we can give the big middle finger to the middle east because we arent burning gasoline.

in the end i decided to run pump gas with methanol injection. at some point i may look into doing the whole e85 thing when it gets more prevalent and more people are making pumps for it.

i hope this helped. if i have made any mistakes, feel free to correct them, its been quite a while since i did this research.

gl with your project

 

A stock FC RX-7 is only rated for E10, which is 10% ethanol. Besides, E85 is 85% ethanol, which is a big deal.

As you suspected, the Mazda6 guy is a dipshit.

Good post.

 

Oooossssshhh, good catch on your part! Wow, I've been mistaken for so long...>.<






To the guy above: Carbon-steel apex seals (Stock Mazda) are NOT the same as the fully carbon apex seals used in race motors. Ceramic apex seals are NOT the same as carbon seals, as you so gracefully pointed out. But no, you weren't right ;D

 

gasoline stoich is 14.7:1

 

Too bad if you run a boosted 7 at 14.7:1 it will blow up because its too lean... haha

 

Alcohol has less energy per gallon, but you can still get more power out of it in a turbo. Your gas mileage will just be lower. It raises your octane and lowers your intake temps. That means you can run much higher boost. Just search for the alcohol injected rotaries and see. They usually have seperate tanks and controllers to add alcohol to the gasoline only when needed, btw. So ya, I know, they still fill up on pump gas. Anyway they make insane power.

The RX-7 owners manual recommends no more than 10% alcohol in your gas to prevent damage to the fuel system, etc. It can also corrode your engine. A lot of gasoline nowadays is ~8-10% alcohol, they just don't advertise it.

EDIT, for below: All Shell gas meets "Top Tier Gas" standards, which means it is 8-10% alcohol (www.toptiergas.com). And I doubt anybody actually uses corn to make the alcohol. Much cheaper to make it from petroleum. Maybe not, I just really doubt it. Oh, and does your '91 coupe have an aluminum hood? If so, what color?

EDIT #2: I doubt Marvel Mystery Oil or Lucas Oil or any hokey oil additive protects against corrossion. Most of those additives are total bunk. Best bet, if anything works, would be to use oil and gas preservatives. Old oil/gas rusts stuff, so guess what they put in those products?

 

Every pump I see in IL says, contains 10% ethanol for cleaner Illinois, except for shell vpower, which is what I use. No corn gas in that.

 

Well I knew not to listen to the masda6 guy when he said that rotary cars can't really run lean and that it doesnt matter in a rotary. And that rotary engines are cool because you can just add on more rotors if you want..."3 rotors, 4 rotors, hell even 5 if they want" - direct quote.

My philosophy is...If they don't have a rotary car, or can correctly explain how a rotary works, or are an actual mechanic that has worked on them, then dont listen to them much. So many people have a lot of wierd ideas about rotary engines, like the ideas above.

 

Good stuff guys... I have done tons of research on this, and the correct answer is:

DONT EVEN TRY IT!!! You will run lean (not too mention the damage to other parts of the car) and ruin your motor. Gasoline is 14.7 stoich, and corn booze runs in the 9 ish range. Our ECUs wont compensate, and the injectors arent even close to big enough.

I inject Ethanol into my fuel mixture, but it doesnt replace my normal fuel supply.

 

just to add an experience to all this when I was a salesman for chevrolet another sales guy sold an 07 tahoe to a nice couple, however he made the mistake of thinking all tahoe models are flex fuel capable (which they are not)

and this was a key selling point to the couple, they bought the truck and started using e85...long story short three days later the tahoe is towed in and because of the damage caused to the motor and the misrepresentation of the car they were given another tahoe which was flex fuel capable...

so yeah... dont even try it.

 

not all of us have turbo power

 

even with a na or turbo..e85 isnt something you wana experiment on unless you expect things to break.