"Safe" Amount of E85 to add

[wordy1]

Before I store my car away for the winter, I'd like to try out some E85 to see how well my car responds to it. What percentage of a mixture can I get away with if I mix it with premium 93 Octane? I have ran toluene up to 25% with no issues. Will I need to up the fuel pressure to compensate for the amount of E85 I add? or is it not a good idea to add any E85 with the components I have and the way the fuel is set on the chip I have? Its basically just a street tuned chip for 15-17 psi with 93 octane with very little timing, its posted in my sig. The car will knock at Full Boost with 92 octane, and worse with 91, it "needs" 93 or better to run right without these issues. I have found that adding a gallon of toluene to a tank of 93 octane is what the car likes the most and was hoping I could substitute E85 instead as its more readily available. How much will my milage go down if I run a more significant amount of it?

Thanks guys... I posted this as well in the E85 section, but no one ever seems to check there, I'd like to get some tonight, if possible, and try it out and get a reading on direct scan.

 

[QUIP'6']

get alky and forget about it. there is no benifir from mixing in your tank because it wil cut the points on octane and the other thing is it is corrosive to your fuel system

 

[Boost231]

get alky and forget about it. there is no benifir from mixing in your tank because it wil cut the points on octane and the other thing is it is corrosive to your fuel system

might want to post this in the E85 Tech. might get more answers there.

 

[wordy1]

might want to post this in the E85 Tech. might get more answers there.

I have, posted in the ALKY section too. I do not have ALKY at the moment, so thats not an option, just wondering if its "ok" to add say 10% E85 to my gas and try it to see if I notice any differences. Is there a reason why it will not mix, correct me if I'm wrong but aren't most gases E10, or 10% Ethanol already?

 

[ronbuick]

Corrosive is a relative term, over time yes, there is a man here who works for Wyoming Ethanol that drives a 79 ford van, he does the mixing for the gas stations here in the Boise area in the big bulk tanks that use E-10 and E-85, he has been dumping
E-100 in his van with with different amounts of gas that is in his tank for the past 20 years, the van has over 300k on it and is still running. But one can always draw your own conclusion.

Ron

 

[wordy1]

Hmm, I am talking about perhaps adding a gallon to a half a tank to try it.. I can't see the harm, but I don't want to mess anything up.

 

[novaderrik]

i've run as much as 14 gallons of E85 in my Regal, and it ran fine except for the lost mileage and a slight sputter for the first 30 seconds when it's started dead cold.
but if i run it 50/50 with 87 octane, i get the same mileage and drivability as 87, with more power than 93 octane.
of course, i've got a mostly stock hot air, so take from it what you will.

 

[wordy1]

Does it matter if I am running 93 octane vs. 87?

 

[novaderrik]

E85 is 105 octane, so with a 50/50 87/E85 mix, you have something like 96 octane.
a 93/E85 mix is 99 octane or so.

 

[wordy1]

I understand the octane benefits, just do not want to do any harm to anything on the car by trying it without first changing things like fuel pressure, my chip settings, etc. as I know the BTU's are about 25% less and the actual consistency is very thin

I would NEVER consider adding 50% E85 unless I had everything swapped out, (bigger injectors, reprogrammed chip, etc.) And if I were you I'd at least be adding some Heet to the tank as Ethanol retains a lot more water than gasoline and can cause some freezing issues.

All I am wanting to know in this thread, is that I am considering topping it off with say 2 gals for a whole tank to up the octane to limit knock issues instead of using toluene for the moment and am wondering if I can without changing anything.

And in the future I am contemplating converting the car to be able to run a 50/50 mix of E85 (mainly because I don't want to have to go to a double pumper fuel pump or MUCH larger injectors, I am going with 60#ers in the spring) and want to try some E-85 before the winter hits to see if it makes any difference before I decide on what I want to do in the spring.

Can I take a direct scan reading to see if there are any changes before and after.. and if everything is "ok" can I keep increasing the percentage with my current set-up?

Its always best to start small. I did the same thing with toluene, but its harder to find and more expensive. And yes I will be upgrading to ALKY in the spring and would like to run a mix of 50/50 E85 on top of that.

Without boost my car runs NOTICEABLY better with higher octane. I think a 50/50 mix of approx. 100 octane fuel with a spray of ALKY at the right time will turn this car into a completely different animal for all applications including daily driving.

E-85 costs less and if I can expect equal milage with a 50/50 mix what more can I ask for? And if I want to really skimp I can mix a 50/50 mix of E-85 and 87 octane like you suggested. I figure that if I have ALKY backing me up, that when I cannot find an E-85 station, I can just drop the fuel % with Eric's chip and keep on keepin' on ..

 

[Daniel Jost]

I run 30-40% E85 in my car, and it runs awesome, its way better running on E85 because i was a tad rich, and when i put that much E85 in it makes it right, and i have a lot more octane. I don't think you will find any problems running 25% e85 in your car, the corrosiveness of it is not very strong especially at that small of an amount. Just make sure to store it with only gas in the winter though, because it will create more water in the fuel tank otherwise after it sits a while.
,Dan