Jump to content
SAU Community

Recommended Posts

Hello everybody. I have no idea where to get a ethanol tester besides online and want to run a e30 mix in my bmw m2. In order for my calculator to work i need to know what ethanol rating the e85 pump is and this is my local station would anyone know or is it negligible to find specifically.

Thanks🙂

United E85 is always 85% ethanol. At least it claims to be.

But that goes out of the window about thirty seconds after you put a tank of it into your car and can't do the math to determine if you have 76% ethanol, or 47% ethanol or 26% ethanol because you put 33L in, then 16L in, then a full tank of 98, then "Some" E85.

Ethanol tunes that aren't full flex or full E85 all the time are just absolutely a waste of time. Don't be stupid and ruin your car.

7 hours ago, Kinkstaah said:

United E85 is always 85% ethanol. At least it claims to be.

But that goes out of the window about thirty seconds after you put a tank of it into your car and can't do the math to determine if you have 76% ethanol, or 47% ethanol or 26% ethanol because you put 33L in, then 16L in, then a full tank of 98, then "Some" E85.

Ethanol tunes that aren't full flex or full E85 all the time are just absolutely a waste of time. Don't be stupid and ruin your car.

So your saying e30 is a wate of time? there's plenty of solid calculators out there that can give you the exact amount flex fuel just re adjusts the tune for you which you wont have to do if you just calculate it accurately. and the point of running e30 over e85 is to not ruin your fuel lines. 

1 hour ago, crustycereal said:

So your saying e30 is a wate of time? there's plenty of solid calculators out there that can give you the exact amount flex fuel just re adjusts the tune for you which you wont have to do if you just calculate it accurately. and the point of running e30 over e85 is to not ruin your fuel lines. 

E30 and E85 will both be reacting with whatever they can. One just has a little less in it and will take a little longer for you to see the things it's reacting with.

Plenty of replacement stuff out there that's ethanol friendly, and then it won't matter what Ex blend you run once you do a full flex tune.

Also fill flex would still be beneficial to you, even for the minor % changes down at E30.

3 hours ago, crustycereal said:

because the cheapest one is over 1k lol

What ECU are you using? The flex sensors I'm used to working with normally cost around $300.

If you don't have a way of tuning the car, how do you plan to safely run e30?

It's not that E30 is bad. I recently did a track day and half of the reason I took ethanol is because when I ran out of jerries, 'some' ethanol is better than none for protection and stuff, even N/A.

The problem with E30 is attempting to maintain E30. It's an akward target to hit and the maths required make the whole thing near impossible very fast.

2 hours ago, MBS206 said:

E30 and E85 will both be reacting with whatever they can. One just has a little less in it and will take a little longer for you to see the things it's reacting with.

Plenty of replacement stuff out there that's ethanol friendly, and then it won't matter what Ex blend you run once you do a full flex tune.

Also fill flex would still be beneficial to you, even for the minor % changes down at E30.

High ethanol concentrations all the time is bad for the fuel system. Not because ethanol has some inherent issue assuming you've done your fuel system setup correctly, but because PIB isn't soluble in ethanol and it contaminates the entire supply of fuel in practice. It is soluble in gasoline so you want to run a tank of normal pump gas every so often to flush all of that out before it causes an injector or something to clog.

5 hours ago, crustycereal said:

because the cheapest one is over 1k lol

From this comment, I'm assuming you're on the MHD platform.

Put it this way, $1k is cheaper than putting a hole through the block.

5 minutes ago, Dose Pipe Sutututu said:

From this comment, I'm assuming you're on the MHD platform.

Put it this way, $1k is cheaper than putting a hole through the block.

I would never run E85 without an ethanol content sensor. Just not worth the headache. Having to reflash the tune and only refill the tank when it's very nearly empty is super annoying.

  • Like 1
11 minutes ago, joshuaho96 said:

I would never run E85 without an ethanol content sensor.

Plenty of people have been doing exactly that in Australia for many years.

All it takes is to only fill up at servos with E85. And that is not that difficult. I drive past several such every day.

The main pain is the consumption rate and having to fill up more often and stash more jerry cans in the shed.

35 minutes ago, GTSBoy said:

Plenty of people have been doing exactly that in Australia for many years.

All it takes is to only fill up at servos with E85. And that is not that difficult. I drive past several such every day.

The main pain is the consumption rate and having to fill up more often and stash more jerry cans in the shed.

Yeah, but in the US if you do this it's almost guaranteed you get the infamous black goo buildup in intake ports and E85 fuel stations while relatively common are nowhere near as readily available as E10 premium unleaded. E85 is also not regulated that well out here. Lots of places "E85" is actually as low as E50 in the winter to reduce cold start unburned fuel emissions. E85 especially doesn't do well with short trips, Mike Kojima at MotoIQ documented how his daughter's EJ25 running E85 experienced stuck rings from being driven short distances and the crankcase was filled with a thin layer of condensation + oil emulsion as well despite very aggressive oil change intervals.

3 minutes ago, GTSBoy said:

Which part of this sounds like the wrong thing to do?

I'd say, almost all of it.

Not wrong, but if I expected to not drive the car for a while but do a fair amount of garage shuffling I wouldn't run E85. Flashing a tune every time that happens sounds like a headache compared to a single map + flex fuel sensor.

1 hour ago, joshuaho96 said:

Not wrong, but if I expected to not drive the car for a while but do a fair amount of garage shuffling I wouldn't run E85. Flashing a tune every time that happens sounds like a headache compared to a single map + flex fuel sensor.

It would be harder to drop the tank of fuel, then plug in a cable and hit "load tune".

The difference is, the change you are saying you'd do only removes the easiest part of the whole operation...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • If you are keeping the current calipers you need to keep the current disc as the spacing of the caliper determines the disc diameter. Have you trial fitted the GTS brakes fit on a GTSt hub or is this forward planning? There could be differences in caliper mount spacing, backing plate and even hub shape that could cause an issue.
    • Hi there I have a r33 gts with 4 stud small brakes, I'm going to convert to 5 stud but keep the small brakes, what size rotor would I need?
    • First up, I wouldn't use PID straight up for boost control. There's also other control techniques that can be implemented. And as I said, and you keep missing the point. It's not the ONE thing, it's the wrapping it up together with everything else in the one system that starts to unravel the problem. It's why there are people who can work in a certain field as a generalist, IE a IT person, and then there are specialists. IE, an SQL database specialist. Sure the IT person can build and run a database, and it'll work, however theyll likely never be as good as a specialist.   So, as said, it's not as simple as you're thinking. And yes, there's a limit to the number of everything's in MCUs, and they run out far to freaking fast when you're designing a complex system, which means you have to make compromises. Add to that, you'll have a limited team working on it, so fixing / tweaking some features means some features are a higher priority than others. Add to that, someone might fix a problem around a certain unrelated feature, and that change due to other complexities in the system design, can now cause a new, unforseen bug in something else.   The whole thing is, as said, sometimes split systems can work as good, and if not better. Plus when there's no need to spend $4k on an all in one solution, to meet the needs of a $200 system, maybe don't just spout off things others have said / you've read. There's a lot of misinformation on the internet, including in translated service manuals, and data sheets. Going and doing, so that you know, is better than stating something you read. Stating something that has been read, is about as useful as an engineering graduate, as all they know is what they've read. And trust me, nearly every engineering graduate is useless in the real world. And add to that, if you don't know this stuff, and just have an opinion, maybe accept what people with experience are telling you as information, and don't keep reciting the exact same thing over and over in response.
    • How complicated is PID boost control? To me it really doesn't seem that difficult. I'm not disputing the core assertion (specialization can be better than general purpose solutions), I'm just saying we're 30+ years removed from the days when transistor budgets were in the thousands and we had to hem and haw about whether there's enough ECC DRAM or enough clock cycles or the interrupt handler can respond fast enough to handle another task. I really struggle to see how a Greddy Profec or an HKS EVC7 or whatever else is somehow a far superior solution to what you get in a Haltech Nexus/Elite ECU. I don't see OEMs spending time on dedicated boost control modules in any car I've ever touched. Is there value to separating out a motor controller or engine controller vs an infotainment module? Of course, those are two completely different tasks with highly divergent requirements. The reason why I cite data sheets, service manuals, etc is because as you have clearly suggested I don't know what I'm doing, can't learn how to do anything correctly, and have never actually done anything myself. So when I do offer advice to people I like to use sources that are not just based off of taking my word for it and can be independently verified by others so it's not just my misinterpretation of a primary source.
    • That's awesome, well done! Love all these older Datsun / Nissans so rare now
Ă—
Ă—
  • Create New...