OZZYAMG

Hi

Does anybody know if I can use E85 which is 107 Octane fuel in a modded E55? I have all the usual mods which can be seen below in my signature.

This petrol is available local to me and is very cheap but I don't want to use it if it will damage anything.

Regards,

OZZYAMG

e500slr

You have to get a tune for it and I'm sure you'll need much bigger injectors and maybe a fuel pump upgrade. Then there's the corrosion issue. I've seen how they prepare flex fuel cars, the lines and all that are made to resist the alcohol.

You can't put the fuel in and go though. E85 needs to be tuned for.

60nomad

Absolutely not to be used. Car wont even run on e85 if I am not mistaken! As said above, it needs to be tuned, but benz aren't that easy to get to run on e85. The whole fuel system needs to be changed or something like that.

James M

Running E85 shouldn't be a problem, but as mentioned before you will need a remap and a dual fuel management system to change between whatever you are running at the time.

BC928

Each car will react differently, and some better than others.

Technically any car made after early 2000s should be able to handle ethanol in large quantities.

We already have some good stuff (ss fuel rail, modern injectors, good resistant tank) , but other things may need to be watched and checked. Chawkins seems to have some good info of his trials with e85.

Personally I have run my other enthusiast car for many 1000s of miles on e85, and have much experience and stores- but as I said each car will react differently.

The fuel pumps would be a concern as is what material is for the lines between the right and left side fuel assemblies on the tank.

e500slr

Like I said, you will definitely need to upgrade the fuel system and tune for it but this will have ALOT of advantages if you pull it off.

E85 has much much much better anti knock properties. It burns cooler, it lowers intake temperatures and allow you to make much more power. It will consume alot more fuel but that's now the point and E85 isn't that expensive, I think it's actually cheaper (I'll have to check, I have a gas station that supply it around 2-3 miles from my house).

mr747

You will have to upgrade your whole fuel system
Maybe speak to eurocharged or weistec about the upgrade

I would be very interested as-well

cetialpha5

I think it depends on the area. Because ethanol is more expensive to transport, if you're far from the source, it is probably more expensive. Keep in mind that regular gasoline is E10 these days which is about 110k BTU's per gallon. E85 is 81k BTU's per gallon so even though it's cheaper per gallon, you have to factor in cost per btu. And when you do that math, it may be more expensive. Also at one point the EPA tried to make E15 standard instead of E10, but many car manufacturers argued against it so that proposal was dropped. The EPA was the one who said that it was probably fine for cars made after 2000. However I wouldn't run E85 on any car that isn't designed for it. The cost of modification would be so high that it'd probably be cheaper to buy a flex fuel vehicle in the first place or the savings in the lower cost of the fuel just isn't there to justify any conversion.

e500slr

That's not why people run E85.

There are 2 kids of people who run E85:

1. Hippies looking for an environmentally friendly bio fuel or hipsters who wanna pretend they care because it's trendy.

2. Horsepower freaks who want a race gas alternative and want to get maximum performance from their vehicles.

It will consume more fuel no doubt. More trips to the gas station should be expected but E85 has ALOT of advantages when it comes to performance, safety and reliability.

BC928

You are completely missing the science behind the reasons FOR using the fuel. BTU is not the reason.

BC928

I think we are even lower than this level of understanding for most on this forum. I think we still have to start sentences like " ethanol is not methanol and is not corrosive" before going further.

Natural rubbers and uncoated aluminum is mostly the only problem.

cetialpha5

You are quoting out of context. The message I was replying to said that E85 was cheaper. It's only cheaper if the cost per btu is lower. Per gallon it's always been cheaper than gasoline, just not per btu. Nothing was said about the merits of using the fuel. Other people in the past have talked about converting non flex fuel cars over to flex fuel, but few have done it due to the cost/benefit analysis. Yes it could be done, but there are cheaper ways to get a lot more hp for less money which is probably why you never see any cars for sale that have been modded to run E85.

BC928

Cheaper ways to get more hp for less money (reliably?)

My point usually is that people are using un-researched information to make judgements about the fuel itself. I will not argue BTU numbers - this is fact. Efficiency is a complex computation, and is NOT only down to BTU. 13:1 compression AND boost - make just as much power with a smaller engine.

I've digressed.

"modded" - Ethanol is not corrosive. It can exist in out gas tank. It can exist in our fuel rail. If the rail is plastic (ugh) as it is in some GM vehicles, the plastic is usually cross linked polyethylene - which makes it perfectly fine. Rubber softens only when it is natural rubber. If the rubber is Flouro-based, which most are - you are fine.

Fuel pump internal seals are a problem.

Being "modded" to run e85 - its not like making a diesel run on veg oil.

Anyway. Great Fuel. You can't buy cheaper fuel that has this high of an octane rating. The decision is dual fuel or go just on ETOH.

cetialpha5

I'm familiar with flex fuel vehicles like the Ford Taurus. The difference between that model and the regular one was that they changed out fuel hoses/fittings and also put in a fuel sensor to determine the percentage of ethanol/gasoline that the engine was burning so that the engine could adjust the fuel injectors and the timing. Costs for the manufacturer was just a couple hundred, but I think it's a lot more for the end use to do it after the fact. I don't think Mercedes made a flex fuel E class although they made some C class ones so I think it would be quite a project to converter one over, especially if the parts/engine coding don't exist.

BC928

One would just go on the assumption there are no OEM parts and just follow best practices.

A fuel system that is pre-direct injection is a very simple system, whether it is returnless or return.

Provide pressurized fuel flow to the fuel rails, and filtering. Oh - and fuel level.

There is no ECU operation for measuring oxygen in the fuel as in a flex fuel car, so there is no reason to focus on those expensive sensors - and most of the time, they are too restricted for performance vehicles anyway.

No Natural rubber, and no unanodized aluminum in the lines. Fuel pumps must be ETOH compliant and if there is any wiring in the tank, it must be ETOH compliant as well.

Done.

Tuning is another story, but people are tuning for all sorts of things.

e500slr

WTF are you talking about you idiot. I never said it was corrosive to metal. I ment the rubber in the first place. So why don't you watch you mouth before telling me you're a know-it-all and we know nothing. You don't like this forum, GTFO then. I've seen what E85 does to rubber parts throughout the fuel system first hand.

BC928

And above is the other problem with what is mostly a fine forum with fine people. If you read the original post, you would see I was defining conversations that need to happen here.

You unfortunately portray the worst of the internet AND of Mercedes Benz owners in one little post! Congratyourwelcome!

"Watch your mouth" Is it 1962 and are you a scotch swilling bald guy talking to his deadbeat grandson?

I have mentioned natural rubber already. And my post was in agreement with yours prior. But please - play through.

95ONE

I have fought these issues, discussions, and misconceptions.

The cost of turning my car into E85 was about $4.00 in seals. A couple fuel filters and replacement hoses. A set of injectors to cover the 30-35% increase in fuel needed (Only at full throttle) and a Fuel pump with enough capacity.

Total Cost was $600 for the Subaru, and a little more for the Porsche to switch out more of the older parts.

I can tune well enough and have friends who are experts in this field, so I am cheating a little.

Overall fuel mapping adds about 25% more fuel. The cost of 93 octane is about 25% more than Ethanol. Works out great.

Compare that to a race fuel and the benefits are ridiculous.

And BTW, comparing only BTU's is ridiculous. Not that any of you did say this, but I see it all the time in forum discussions.
Knock resistance and heat latency play a large role in the comparison also.

On a last note, the last I heard, the octane of E85 is around 104. I think a lot of people are saying 107 because of the latency of heat characteristics make it ACT like an Octane of around 107 or higher.

OH! And.. I DID just sell my Subaru tuned and running on E-85. There are many E-85 Stations in Houston, and that might make all the difference.


Just and FYI to horsepower difference between 93 octane and E-85.

Exact same set up. STI motor and Stock STI turbo
93 octane. 18psi Max HP = 297 awhp Detonates with any more pressure above 18.
E-85 21psi Max HP = 340 awhp Doesn't detonate and can boost spike (with no increase in power)

= 15% more power than Gas.

Guestimate on the AMG Supercharged V8
(less increase because roots blower vs turbo efficiencies)
93 octane = around 520whp
E85 (+10%) = around 572whp.

BC928

SPEAK! I say brother... SPEAK! Testify!

Exotic-metal55

You can run E85 and I ran my car on it a few years back. Boosted engines love E85 but here are the dangers and problems.

1) You need to upscale your injectors, pumps and fuel lines at least 30% over your tuned hp, as E85 , in simple terms has less energy per gallon. Also monitor AFR and fuel pressure with the new set up and adjsut for any fuel weakness.

2) Here is the big challenge With E85 here in states, at the pump, it can very in % a lot during the year and if you fill up in the summer, tune for it and then go fill up again, with maybe a higher % of corn gas, then you will lean out big time. The safest way to use pump E85 , is to install an alcohol sensor system to change your tune per % of alcohol detected but this may be a challenge on our cars, even though most modern cars come with this sensor already.

3) The last thing to do, if you are are dead set on racing and using E85, is to buy C85 and that is the race version of E85 that always stays at a steady fuel ratio. Expensive and hard to keep enough 55 gallons drums around, unless only race.

Mr. CVE

^^^^
this is very true.
I used to use it on a few cars I tune, and used to sell it.
We only used drum stuff, due to it being consistent.

BC928

All very correct. Can't disagree at all. I will say that the % change can be made somewhat less worrying with a few points and work-arounds:

1) ETOH is ridiculously forgiving on AFR. As long as your plugs are well buried then you can run whatever safety margin you would like - to the rich side. Technically speaking, the richer you are, the more torque will be made with ETOH.

2) I am always sure to remember that AFR is not universal, if you are thinking of numbers like 14.7 or 12.5 - only LAMBDA is universal. In which case stoichiometric is 1.0. With e85, lambda 1 is 9.7. With petrol its 14.7 - but still lambda 1.

It can get confusing - as you are looking at a petrol based scale readout of AFR while running E85 - this is why the real good guys that switch fuels think in lambda. F1 thinks in an "equivalence ratio".

3) So you can put e85 in there, and it may end up being e68 or e89, and within reason (the math on the change between those amounts and what it means to AFR is... math) - as long as you put in some good solid safety in the AFR, you are good.

Anyway. Great stuff.