E85 - Experiences and opinions.

[Bubu]

By now you have probably heard of E85 fuel being introduced at several service stations. The claim is that E85, an Ethanol blend is higher octane, upto 105 RON at Caltex.(Caltex rolls outs E85 | carsguide.com.au (http://www.carsguide.com.au/site/news-and-reviews/car-news/caltex_rolls_outs_e85))

I been reading a bit and a few guys in their EVO's have been getting good power increase by running E85. The kms per tank is not quite as good and you may require an upgrade of injectors and fuel pump. Im not sure what the Audi/VW/Skoda injectors of each respective model flows. Although I have not checked it out personally, E85 is cheaper than 98 Premium.

Have you guys tried it or considered trying it out in your VW/Audi/Skoda? Or do you know someone who has tried it?

[noone]

Odd. Some of the Ford / Holdens that can take it where using something like 40% more fuel... Sounds odd...

[brad]

If you are serious about making power then you need to know how much headroom you have in your injectors as e85 needs about 30% more than your current max actual flow. If you have (pulls figures out of air) 300 rated injectors but the maximum you ever actually flow is 250 then you need to flow an actual of 325 & will need to go to 350 or even 400.

Expect to go through about 30% more fuel. You will make lots more power providing you tune for it.

As you can see from the above, I only have half a clue about the whole thing. :-)

[gmx]

Odd. Some of the Ford / Holdens that can take it where using something like 40% more fuel... Sounds odd...

lol.

normal.

[gavs]

Motor magazine did a test on a née e85 ss-v and found that there was no clear benefit in regards to fuel consumption or power in a car that is programed to use e85. I'm not sure about now, but VAG has so far had the stance of no ethanol.

[Bubu]

Motor magazine did a test on a née e85 ss-v and found that there was no clear benefit in regards to fuel consumption or power in a car that is programed to use e85. I'm not sure about now, but VAG has so far had the stance of no ethanol.

Which issue of Motor mag was this in?

I find it strange that there was no power increase in a car tuned for E85. A couple of weeks ago I was at IS Motor Racing where my mate was getting his Evo tuned. The guy that was tuning it said he could not get more than 216kw at the wheels with the current mods, unless my mate changed injectors and ran E85. With E85 he said he should be able to get somewhere between 230 and 240 kw at the wheels.

[John2204]

I was running 245kwatw with my Evo 9, changed injectors and tuned on E85 and got 285kwatw @ IS Motor Racing :) corn fuel was the bomb!!!

[McCoy]

The fuel you are referring to is what Caltex call E-flex meaning it's a flex fuel. A Flex Fuel can vary anywhere from E70 to E85 dependent on if it's a summer or winter blend fuel, at least that's what the marketing, carpet strolling types will tell you. In tuning cars I have not seen a summer or winter blend, I've just seen huge variances in the fuel regardless of the season, which isn't a good thing as far as I am concerned.

In my opinion running an E-Flex fuel leaves you know choice but to run a Bioadapter because of such changes in the fuel blend, added to that you are never sure what RON they have blended with. Take for example E85, its 85% Ethanol and 15% what? 91, 95 or 98? You'll never know at the pump.

Running a Flex Fuel can very quickly turn into good times gone bad!

Previous posts are correct; you'll need a retune as it behaves very differently. With 98 for instance, you go to rich with AFR's and you have the possibility of fouling plugs, go to lean and the engine goes pop. With E85, you go to lean and engine goes pop...go to rich, it also goes pop.

Bigger injectors are something you'll need to look at as I doubt you'll have the headroom in the standard injectors, pulse widths and Duty cycles will give you a clear indication of how much headroom you have and where you'll end up with a fuel change. As far as increased usage ,it's close to 30%, slightly less around the 27% mark if I was to use an average, again that's just what I've had exposure too.

That's about it as far as negatives go, the positives are its easy power, and oh what power! I've seen an injector change and a switch of fuel from 98 to E85 gain over 60kW at the wheels, so it's cheap and easy power. It runs cooler and cleaner (big debate about that though) although you do need to be careful of lines, pickups etc. used and storage is an issue since Ethanol blended fuels are more Hygrospic than most other fuels.

If you were going to use it, I'd suggest not using a flex fuel but a blended fuel you have some trust in. Race fuels Australia (ELF) sell the stuff but it's expensive at $2.50 a litre, at least you know what you are getting is going to be a good thing I guess. I know I've used their product before and it's a good thing, in a motorsport application it's a no brainer.

For road cars though? I'm not so sure.