85% Ethanol VS 91 Octane

[Phalanx99]

Anybody know the advantage and disadvantage of each type of those gasolines ?

 

[tight_tsi]

All I know is you can't run the E-85 in a non-flex fuel vehicle - will run like crap and cause cel lights to come on.

 

[underradar92]

Here is a thread on E 85. http://dsmtuners.com/forums/showthread.php?t=227626&highlight=ethanol+fuel It seems no one really likes 91, however the rather involved tuning needed to run E 85 exclusively is a downer. You living in MN gives you a strong arguement for giving it a go. I think one could have a tune in DSMlink for both fuels, in case you couldn't find one or the other. Here is another. http://dsmtuners.com/forums/showthread.php?t=239526&highlight=ethanol+fuel

 

[T_K]

To convert to E85 you have to pretty much to upgrade/change your entire fuel system and you better have some good engine control electronics. It's something I've been thinking about but there's no E85 here in NJ at this time.

 

[Phalanx99]

I consider about E85 because I just read an article on a fully rebuilt Elise that runs on E85. The performance is difference from E85 and 92 octane. They said that with E85 the Elise push down more 46hp and some torque that I forget.

 

[Phalanx99]

Oh, BTW, I just turboed my 4G64 and I am using DSMlink. So is it better if I switch to E85 ? Any performance wise ?

 

[Phalanx99]

I know that we have to change the fuel filter and change all the rubber hoses to stainless. Anything else ?
One more question, I am running a 60 trim on my stock 4G64, 550cc injectors, and stock Evo VIII fuel pump. So can I use E85 ?

Thank you

 

[jking29]

To run E85 with a 60 trim would require a minimum of 850 injectors, a larger fuel pump like a Walbro 255 or Supra fuel pump as well as a chip and a afc or DSMlink to tune it. But it will probably make another 30 hp above what 100 octane race gas will make.

 

[Dark_Horse]

To run E85 with a 60 trim would require a minimum of 850 injectors, a larger fuel pump like a Walbro 255 or Supra fuel pump as well as a chip and a afc or DSMlink to tune it. But it will probably make another 30 hp above what 100 octane race gas will make.

Even 850's are too small for a 60 trim, you should use minimum of 1000cc injectors. 850's at 90% IDC have a max lb/min of ~42 on E85 (figuring E85 FAR is 8.05:1 which equates to 12:1 on gasoline).

There's an Excel calculation page http://www.rmdsm.org/forums/showthread.php?t=6385&page=3&pp=10&highlight=e85 that I made. Post# 23. The post explains basically how the calculations page works. This should give you an idea of what you need depending on what lb/min your turbo will flow.

 

[Bmxr152]

what would happen if you mixed e-85 and gasoline. Say 1 gallon E-85 to 5 gallons 91 octane, would that work like race gas?

 

[Dark_Horse]

what would happen if you mixed e-85 and gasoline. Say 1 gallon E-85 to 5 gallons 91 octane, would that work like race gas?

To find the resulting octane of blending E85 & 91 octane, multiply the amt of gallons E85*105 & add to gallons of Premium*91 & divide by total gallons.
So (1*105)+(5*91)/6=93.33 octane.

All that to say that E85 & gasoline are ok to mix.

 

[bertrenolds]

I was just talking to a guy that races open wheel on a non-turbo volks wagon engine and he seemed to think the running 91 octane instead of E85 would produce more HP on a 14b running 950cc injectors. He said the BTU's I believe are alot lower for E85 compared to 91octane so even though I could increase boost alot more I would still come out even with 91octane because of the fuel ratio of E85 and I would need bigger pistons and a more aggressive cam shaft to see a difference. Anyone care to explaine to me what I sould have told him?

Also, really old thread bump but this is what google gave me. He said I could ask and physisist and he would explaine to me why E85 isint all it's cracked up to be.

 

[Bud92gsx]

E85 increases hp and lessens knock..Which can allow you to run more boost..But the car has to be tuned for it..Unless you add a couple gallons of e85 here and there..

 

[DsmDanny98]

You need to have the proper vehicle components (Injectors, fuel pump, etc.) and the right tune for E85. It allows you to run more boost than 91 octane. Only issue is you need to find pump stations around you that provide E85

 

[phunny]

E85 increases hp and lessens knock..Which can allow you to run more boost..But the car has to be tuned for it..Unless you add a couple gallons of e85 here and there..

^^^Exactly. Although E85 is sooo worth it you must also be careful. E85 is so knock resistant you really won't knock so with that being said make sure you don't go crazy on your timing and melt your pistons.

 

[blaze12]

I think E85 or corn juice just has a really high octane rating which is good for turbocharged cars .The higher the octane rating the higher the the temps can be in the combustion chamber , so more boost ,. See if it gets to hot then you get knock or pre ignition before , when the plug fires before the piston is a few degrees before top dead center and if it does it knocks and ecu reacts and retards the timing which isn't good when talking about performance.

 

[DSM1G90]

Called "BTU output" Alcohol has a high octane but the BTU output is so much less than regular fuel. And it's the BTU that gives fuel the power needed for the work required.

Take a sample (not actual BTU readings) number here: E-85 would have about 5000 BTU output due to the high content of alcohol, whereas 87 regular has about 8000 BTU since it burns hot and clean, but obviously less octane. Why E-85 gives you much less miles per gallon since it takes more fuel to match the BTU range of 85/87.

I'm not at all impressed with E-85 due to more fuel has to be purchased even though the price is cheaper per gallon. Thus, you either break even, or even pay more per gallon by using E-85. It was basically designed for cleaner emissions-a gov't thing once again...

91 and 93 fuels just have higher antiknock compounds added over what 85 would have - why 91 and 93 fuels actually burns more dirtier due to the additives needed to prevent knock.

 

[donniekak]

Called "BTU output" Alcohol has a high octane but the BTU output is so much less than regular fuel. And it's the BTU that gives fuel the power needed for the work required.

Take a sample (not actual BTU readings) number here: E-85 would have about 5000 BTU output due to the high content of alcohol, whereas 87 regular has about 8000 BTU since it burns hot and clean, but obviously less octane. Why E-85 gives you much less miles per gallon since it takes more fuel to match the BTU range of 85/87.

I'm not at all impressed with E-85 due to more fuel has to be purchased even though the price is cheaper per gallon. Thus, you either break even, or even pay more per gallon by using E-85. It was basically designed for cleaner emissions-a gov't thing once again...

91 and 93 fuels just have higher antiknock compounds added over what 85 would have - why 91 and 93 fuels actually burns more dirtier due to the additives needed to prevent knock.

I run it, and am very impressed. Price wise, it compares to 110 octane $10+ a gallon race gas, not 91 craptane.
As far as btu, it actually makes more power than gasoline. Although it has a lower btu rating, you burn so much more of it, that you get about a 5% power increase.

http://iqlearningsystems.com/ethanol/downloads/Racing Fuel Characteristics.pdf

 

[bertrenolds]

I have all the mods, I just need to decide if I'm going to run it and as of right now I'm going to. I live in MN so plenty of corn juice, 950cc injectors, walbro 255, AFPR, dsm link, FMIC, ported 3'' exhaust, 14b turbo. I guess I can always go back to 91 octane.

 

[Black-Out]

I run it, and am very impressed. Price wise, it compares to 110 octane $10+ a gallon race gas, not 91 craptane.
As far as btu, it actually makes more power than gasoline. Although it has a lower btu rating, you burn so much more of it, that you get about a 5% power increase.

http://iqlearningsystems.com/ethanol/downloads/Racing Fuel Characteristics.pdf

+1 on that.....basically it's the poor mans race gas solution.....down here there are many cars that run on E-85 and I definitely don't recommend using a gallon here or a gallon there because to properly use E-85 as your fuel you must use as much as 40% more fuel and throwing a little in with your 91-93 octane tank can cause you to run lean and risk your engine because at a given injector size x amount of injector pulse width is needed to maintain your afr's and mixing in a less volitile fuel means you'll need more of it to produce the same effect...you'd have to have the car tuned for the exact mixture and then you'd have to maintain that mix ratio every time you filled the tank which just isn't feasable for convenience sake .....it takes deliberate planing to pull it off the right way and usually more than one map to ensure you don't tear up an engine over the idea that you can make more power......

More over if you use your normal 255 walbro pump your normal lines and injectors and a tune the car will run fine, but you need to keep in mind that you don't want to leave it in the tank for extended periods of time because it will eat away at petroleum based products (plastics,rubber,ect,most of the other materials found in your fuel system) it's best to run it on race night then swap back over to normal fuels which are fuel system safe to help prolong the life of the fuel system (eventually you will kill a fuel pump or injectors and so on because the components just aren't designed to run on E-85)

If you go this route you need to start with a hard horsepower goal and from that point you need calculate BSFC (brake specific fuel consumption) which will give you the injector size you'll need to run to achieve said power goal at no more than 85% duty cycle.......

These are just my personal experiances with E-85 and they aren't dead set as atmospheric pressure,temp and humidity as well as a bunch of other factors impact the out come..... that said if you go down this road you need to be 100% sure you know what your doing or you'll have more head aches than anything else.... E-85 is only as good as the thought process that went into the set up.....

Hope this helps....just my lengthy .2 cents...