Need advice on E85

[bsalis]

Anyone tried running Ethanol (E85/Flex) in Australia with an NC? Does anyone have experience with this or have a knowledge about the pitfalls and gotchas?

I have been thinking about converting/tuning my NC to run on Ethanol. So E85 or whatever sub-85% mix you end up with (Flex-fuel), either from Winter E85 or filling with regular unleaded. I'm really keen to switch over but there seems to be some problems where if you try and deal with one, you make another worse!

First problem is with the tune. EcuTek RaceRom does not support Flex-fuel for the MX5 just yet (but other cars are supported - damn you again Toyobaru Twins!). However with RaceRom, I can have 4 seperate maps to cover different mixes, so I could have 85%, 70% (for winter E85), 10% and 0%. This could possibly work if I use up the tank, then fill to full so I have a known ethanol mix. But this brings me to the next problem...

That is the problem of availability. It seems United and some Caltex sell E85. This does not give me many options, and there will be times that I will be forced to fill with regular unleaded. This may be hard to do if I need to make sure the tank is almost empty (mainly when switching back to E85).

The final problem is my main concern, and that is water absorption. My NC is not a daily driver, so if I am filling to full on E85, then that fuel may sit in the tank for some time... maybe even weeks. From what I have read, this is a pretty bad thing to do.

Yeah, so anyhow... any thoughts or experiences with this awesomely tempting devil fuel is welcome. Some other questions to put out there around this topic...

* Is water absorbtion a serious issue with modern E85? Is rusted injectors (or other parts) a real problem?

* Other then a tune (and ethanol mix detector for flex), what other changes should I investigate or expect. New injectors? Fuel pump? Fuel filter? Is there magic do-not-rust injectors to deal with water?

* I have read that ethanol frees up gunk in fuel filters - any truth to that?

* Anyone have on-the-ground experience with availability of E85? Is it as bad as it looks? Do places that say it is offered actually have it available when you show up?

* Anyone know when EcuTek RaceRom will support proper Flex-fuel? Or know of ways to just deal with variable mixes in a proper way?

TL;DR I want to run my NC on Ethanol - tell me why I am crazy, or not.

[NitroDann]

Its a fuel, put it in, tune it and drive it, keep a wideband displayed to make sure the blend is ok.

not a lot of point unless you crank the comp and cams, or you know, turbo it.

[Magpie]

* Is water absorbtion a serious issue with modern E85? Is rusted injectors (or other parts) a real problem?
- If you go flex fuel path then drain out the E85 if the car will be sitting for a long time. Or make sure the tank is as full as possible to reduce the surface area that the E85 has to absorb. I have left E85 in my car for at least 10 days with no issues.

* Other then a tune (and ethanol mix detector for flex), what other changes should I investigate or expect. New injectors? Fuel pump? Fuel filter? Is there magic do-not-rust injectors to deal with water?
- E85 uses a lot more fuel hence other upgrades may need to be considered. E85 can be 'hard' on fuel lines so consider using hoses that are designed for flex fuels.

* I have read that ethanol frees up gunk in fuel filters - any truth to that?
- I have read that non race car drivers got laid more in high school. Make sure your tank is clean before you switch and do regular changes on the fuel filter.

* Anyone have on-the-ground experience with availability of E85? Is it as bad as it looks? Do places that say it is offered actually have it available when you show up?
- United and Caltex sell E85. Just be aware of the standard for E85 it can be anywhere from E70 to E85. If concerned use drum E85 but be aware of the local authorities rules on fuel storage. If you go flex fuel path then availability is not an issue.

* Anyone know when EcuTek RaceRom will support proper Flex-fuel? Or know of ways to just deal with variable mixes in a proper way?
- PASS. To use flex fuel you need to have it tuned on 98 and E85 the ECU then does its magic based on the ethanol content. Maybe with the EcuTek you can only tune on E85 OR 98 and not both. Others should know this answer.

What is the motivation to go E85? Performance? Cheaper fuel cost? The fantastic smell of E85 when it is burnt? The amount of water sent out the exhaust?

As for Dann there are other ways to get performance gains (cams, compression, forced induction).

[Dan]

* Anyone know when EcuTek RaceRom will support proper Flex-fuel? Or know of ways to just deal with variable mixes in a proper way?
- PASS. To use flex fuel you need to have it tuned on 98 and E85 the ECU then does its magic based on the ethanol content. Maybe with the EcuTek you can only tune on E85 OR 98 and not both. Others should know this answer.

A decent tuner should be able to give a single Flex/E85 tune without the need for a sensor to determine the content. The car will run slightly richer when on E70 rather than E85 due to the higher concentration of petrol which is what you want anyway and as long as the timing isn't set so wild that it won't work on E70 then it will be fine. Many people (including me on my other car) have been running this way for years.

The only thing you have to be concious of is not filling up until your tank is basically empty when switching fuels which means you either need to time getting to the Servo at just the right time or have a Jerry Can with you and do the switch on the side of the road or at home. The way I achieve switching from 98 to Ethanol is to use E85 for the switch and wait until the second warning pops up on my car which indicates I have about 5L left meaning if I fill up my 57L tank with E85 I'll still have a higher concentration than E70 in my tank and when switching back to 98 I do the same thing waiting till the last bar but instead of filling the tank I just put 20L in, drive the car till the last warning light comes on without doing any hard acceleration and then fill it up with 98, this process takes the ethanol concentration down to around 2% which should be safe to run on my 98 tune. Sounds a bit pedantic but it's expensive to get a new engine and I don't swap often.

OP - What's done to your car?

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[Apu]

I did consider going down the E85 path but:

- availability around my area is an issue
- my car (turbo NB) sometimes sits around for a month...or more!
- when I do go for a drive, I want it to be a long drive...E85 availability an issue again (I'd really prefer not to mix fuels)

So I went for water-methanol injection. The car will happily run on 98, and will gain 13rwkW with the system turned on. If I run out of water-meth, I can fill up with distilled water - I'll still make some gains, but not as much as 13rwkW. This is however dependent on your tune / setup.

No long term maintenance issues, no worries about availability.

[madjak]

I saw 6-8% hp gains across the entire rev range from switching to e85 on a n/a engine. For me it was definitely worth it as it was a very easy upgrade, plus I can get e85 from a United station about 10 mins away from my home. I'm running a flex sensor via a Haltech ecu. The tuner said for n/a vehicles you really only need about 40% ethanol to get all the gains, from there the timing is as far as it can go.

A couple of things I've noticed are the smell of the fuel, the engine runs a bit cooler, and also my exhaust is slightly louder running on e85. I also have to take more fuel to events.

So far I have only changed fuel lines from the hard lines forward and kept the stock rubber lines on the fuel tank but at some point I will switch them out too. So far I'm very happy with the switch, that extra power really helps when n/a and is worth the extra hassle for me.

[Magpie]

Both madjak and myself run the same setup on naturally aspirated (Haltech/flex sensor) and I agree with what he found in general for a HP increase when using E85. However our engines are not what would be considered stock and the HP gain may not be the same for the OP.

In general I don't mix fuels, rather I have a quick system to pump out the existing fuel and replace with the other. The flex fuel sensor is useful if I get stuck without the right fuel being available.

[bruce]

As you have so many concerns, I'd say no. There is no benefit in your situation.

[The American]

Is there any truth to the corrosion issue? People are concerned about leaving ethanol to sit in the tank. I've tried to read the internet on this and have yet to find anything conclusive/scientific...

[lizard]

I did consider going down the E85 path but:

- availability around my area is an issue
- my car (turbo NB) sometimes sits around for a month...or more!
- when I do go for a drive, I want it to be a long drive...E85 availability an issue again (I'd really prefer not to mix fuels)

So I went for water-methanol injection. The car will happily run on 98, and will gain 13rwkW with the system turned on. If I run out of water-meth, I can fill up with distilled water - I'll still make some gains, but not as much as 13rwkW. This is however dependent on your tune / setup.

No long term maintenance issues, no worries about availability.

water-methanol injection what kit did you use ? Details ? photos ??

Thanx

[Apu]

I imported the Snow Performance kit...now that you mention it, I haven't updated those pics to my build thread.

[IanR]

I will be able to weigh in with comments when its done, but the plan is to use the GM Conti Flex sensor from a late model Holden, with ms3 and run two maps, the united e85 and the 98 map, the ecu reads the percentage and adjusts the tune accordingly. So then I can run 98, e70 or e85. The e85 is reported to increase the torque about 20% across the range for the turbo motor. The aspect that appeals is the safety the slow burning ethanol brings to the tune, far "safer" for the motor against detonation when adding ignition than on 98. Just repeating what ive been told but i should have dyno charts to confirm in the next few weeks. Cost of the flex sensor was under 200 from a wrecker, obviously more dyno time as well.

[NitroDann]

Ausbouy's Na6 just went 6 hours double handled at Morgan park making 200rwkw on a stock NA6 engine on E85. Do the math.

[bsalis]

Thanks everyone for the advice and feedback on this. Much appreciated.

OP - What's done to your car?

It's a 2007 with a FM Supercharger (currently pushing 8psi), as well as full Roadstersport exhaust and a CAI. Being an NC, it has the stock ECU tuned with Ecutek. Which from what I can tell, does not support Flex-fuel with RaceROM yet.

Reason I am looking into E85 is for more power. I plan to do that upgrade with a smaller pulley for 10psi or more, and a re-tune of course. Not sure there are many other power upgrade paths left. I'd rather avoid changes to internals, like cams, and with forced induction I'm not sure that's the way to go anyhow.

So I went for water-methanol injection.

That is the other option I am thinking of. Water injection gives you much the same results (higher octane, better cooling), but seems more complicated - just another thing to go wrong. However it is more convienient to use and will work well with RaceROM map options.

As you have so many concerns, I'd say no. There is no benefit in your situation.

Yes I have concerns, I'm just risk averse, and just looking to do this right. I don't mind some inconvenience "because race car".

[Apu]

I had my kit imported through Works Engineering - they are dealer / distributor in Asia so I got trade price on it, haha! We aren't doing it here as there is another dealer.

Installation was done by Mania - Dave says it was quite easy. It has an on/off switch and it's been tuned to pump when boost kicks in.

What I should have done was also set it up to be tuned for water alone...but I don't use the system that often now - only when I want the few extra kW, or when I'm on the track.