Using lower percentages of ethanol... (E20,E30,E50)

[forcefed86]

With the crazy fuel system demands of E85 I was just wondering if pump E85 70-85% ethanol is really necessary? I've seen 1500+hp engines out there running 85% methanol. Few of them local at our drag strip. It seems no one is having trouble with detonation on this fuel at reasonable power/timing levels.

I'm finishing an HX-40 setup at the moment and the thought of running huge injectors and re-vamping the whole fuel system rubs me the wrong way. Currently run factory lines/filter with a TT supra fuel pump and 1000cc injs. Unfortunately they don't have e50 at the pumps here. As I believe that would be the perfect mix for my 500-550hp goals.

I'm wondering how far I can push E30. You never hear anything about the lesser blends. Would be a huge advantage if we could squeak by with e30 over e85 though.

Run single wally 255 or similar with out fear of it falling short.
Could run reasonable sized injectors for great driveability
Retain the factory fuel line setup
pick up gas mileage
lower blends never change ehtanol percentages (easy tuning)


Just a thought... anyone running e30 out there? I may end up trying it out. I'm tired of the crappo mileage anyway.

 

[turboglenn]

although i know some people are doing it i've read very little on those who've added pump gas to the e85 to make an e60 - e70 blend, those that i have read about did it because of running out of injector as i recall.

I'm running 1000's and currently one 255hp (was running 2 of them parallel) but with the larger -6 fuel system the one pump seems to be doing okay for now. I run pure e85 and was making 438hp on my last turbo and running about 80-85% IDC at 12.3-12.5 AFR's

since the install of the 67mm turbo though i've started maxing out the 1000's really easily and have thought about addins some pump gas to gain a few % IDC back on my side, while retiaining enough ethanol blend to keep the knock away/minimal (trying to think of a way to mke it consistant is the issue i always come up with unless you were to always fill the tank from a certain point on the guage and add say 3 gallons pump fuel then fill the rest of the way up with e85)

I have a couple friends who's car's i've tuned that we came to a similar solution for more boost on near factory cars, i would have them always fill up from say 1/8th tank , start with 2-3 gallons of e85 then fill the rest of the way up with pump fuel (these are cars with near stock fuel systems aside from a pump and slightly larger inejctors) These seemed to work really well, 2 in particular were a 2g talon FWD and a 2004 subaru WRX, the talon on the stock management with 5knob AFC ended up being able to run 20-22psi on a 14b daily with no detonation and near full factory advance coming in almost every time. The talon did throw a check engine light from having any more than 3 gallons of E85 mixed in from the 1/8th tank mark because the fuel trims couldn't get themselves in check (running a 5 knob AFC is cruse enough to have helped this pop up though too)

the WRX wwas able to go from 14-15psi and 9-11* timing tops while knocking like crazy according to the cobb acessport log, to being able to pull 19psi and having the timing maxing out at about 15-17* at 12.5 AFR's (great AFR for mainly pump gas with some e85 in it)

Both cars barely showed any signs of knock after the e85/pump gas mix

 

[forcefed86]

As you mentioned It would be very time consuming/difficult to mix your own and get exact percentages. Would be ok for a race car but I'm daily driving mine. Even though people seem to agree E85 is right around 105 octane, it suppresses detonation much better than 105 race gas. I know of many locals previously on c16 that have switched over to e85. And say they actually made more power and could run more timing.

I'm hoping with a good IC and largish turbo (hx40) 500whp levels should be attainable with e30. Which is available at the blender pumps here in KS. I can always up the mix if I know I'll be going to the track or racing. According to the pic below taken in Europe e30 is 95 octane. If that is so, a 1:1 ratio of e85 and e30 would be right at 100 octane and fairly easy to mix.

I just don't know if I can justify the hassle of e85 on a daily driver any longer. I had very similar luck with meth injection and pump 91. I'm sure e30 and meth injection would get the job done.

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[T is for TURBO]

Subscribed.

I too have been wondering about this. My fuel system is almost brand new (950s & a wally 255), and I'd rather spend the money on a FPGreen, start my awd swap, and get the trans rebuilt, rather than fork over more cash for a new set of injectors. There is a station right down the street from where I store my car that sells e25 and I think e40 along with e85. It seems like it could be a happy medium, I would like to hear more about this!

 

[forcefed86]

Subscribed.

I too have been wondering about this. My fuel system is almost brand new (950s & a wally 255), and I'd rather spend the money on a FPGreen, start my awd swap, and get the trans rebuilt, rather than fork over more cash for a new set of injectors. There is a station right down the street from where I store my car that sells e25 and I think e40 along with e85. It seems like it could be a happy medium, I would like to hear more about this!

I think at this point we are going to have to be the test subjects.

If you have e40 available I’d be all over that. Should be plenty of fuel to support 400-500hp IMO. I’d just start with low timing and boost and work your way up. No telling how far you can take it until you try. Start with low timing. I’d suggest something crazy low like 0-5* at peak torque ramping up to 15-18* at redline. Then bump the boost up watching plugs carefully. Once I get the hx40 setup complete I’ll be trying out e30 the same way. I have a new clutch to break in so I won’t get to do any boosted testing for a while. Probably have to ditch my current BR9ES plugs for something warmer.

 

[TSIMonsteR]

I've been running e30 in the talon for a bit now. I finally got a good 16g to replace this nearly blown 14b (burning oil, leaky exhaust housing, etc) so I'll be able to see how far E30 gets me on evo 560s and a walbro 255.

I get about 30ish miles or so less per tank on e30 than 93, but the e30 is much cheaper on a fill up.

 

[T is for TURBO]

I think at this point we are going to have to be the test subjects.

If you have e40 available I'd be all over that. Should be plenty of fuel to support 400-500hp IMO. I'd just start with low timing and boost and work your way up. No telling how far you can take it until you try. Start with low timing. I'd suggest something crazy low like 0-5* at peak torque ramping up to 15-18* at redline. Then bump the boost up watching plugs carefully. Once I get the hx40 setup complete I'll be trying out e30 the same way. I have a new clutch to break in so I won't get to do any boosted testing for a while. Probably have to ditch my current BR9ES plugs for something warmer.

I think your right.

I just did a little research. The place I would get it from only sells regular, E20, and E85. Although the station has a blender pump, so MAYBE, if I'm luck, someone there would beable to blend a E40 or E50 blend. But I think my aspirations are a little to high... Either way, the car is not a DD so, I would have no problem mixing my own fuel, although, I may just want to start out with E20.

EDIT: I can get 93Oct here, but I would start with 91Oct since E20 ~ 91Oct. That way I'm comparing apples to apples.

Unfortunatly I will be putting the car away for winter soon, so I won't be able to do much testing. But If I get the chance, I think I might get a moderate tune on Regular pump 91 (No ethanol added) @ maybe 18-20psi(FP Big T-28), 11:1AFR, and a moderate amount of timing (with no knock of course). Then switch over to E20 using the pump gas tune. I'll be sure to closely monitor IDC, knock, and keep an eye on the plugs.

Do you see any negative to doing this? With the 255 and the 950s I think I would have plenty of fuel to prevent knock, even at a 11:1 afr with E20? And since ethanol should give me more leeway with timming, I should be okay in that department.

BTW, what AFR would I eventually want to run with e20?

 

[DSMReviver]

Not to mention some cars running e85 or more ethanol in them suffers from "goo/tar". The question is what we can get away with running less ethanol and be able to control knock/detonation at the power level we want to make. More gasoline in ethanol certainly helps make "goo/tar" disappear but more powerful cars needs more ethanol to control unwanted detonations.

 

[T is for TURBO]

Not to mention some cars running e85 or more ethanol in them suffers from "goo/tar". The question is what we can get away with running less ethanol and be able to control knock/detonation at the power level we want to make. More gasoline in ethanol certainly helps make "goo/tar" disappear but more powerful cars needs more ethanol to control unwanted detonations.

This is another reason why I've avoided going to E85.

I really wish I had a few more months of good weather to do some testing.

 

[Bud92gsx]

I run about 2 gallons or so of e85 in my 16 gallon tank..I'll add 2 more gallons to the tank for winter since my car sits in it's spot all winter..

 

[forcefed86]

I think your right.

I just did a little research. The place I would get it from only sells regular, E20, and E85. Although the station has a blender pump, so MAYBE, if I'm luck, someone there would beable to blend a E40 or E50 blend. But I think my aspirations are a little to high... Either way, the car is not a DD so, I would have no problem mixing my own fuel, although, I may just want to start out with E20.

EDIT: I can get 93Oct here, but I would start with 91Oct since E20 ~ 91Oct. That way I'm comparing apples to apples.

Unfortunatly I will be putting the car away for winter soon, so I won't be able to do much testing. But If I get the chance, I think I might get a moderate tune on Regular pump 91 (No ethanol added) @ maybe 18-20psi(FP Big T-28), 11:1AFR, and a moderate amount of timing (with no knock of course). Then switch over to E20 using the pump gas tune. I'll be sure to closely monitor IDC, knock, and keep an eye on the plugs.

Do you see any negative to doing this? With the 255 and the 950s I think I would have plenty of fuel to prevent knock, even at a 11:1 afr with E20? And since ethanol should give me more leeway with timming, I should be okay in that department.

BTW, what AFR would I eventually want to run with e20?

All blends of ethanol that I am aware of use 87 octane as a base. If you can get a base of 93 that is ethanol free you can mix up some nice fuel. We are limited to 91 octane here and all fuel has ethanol in it already. I'd speculate the the 89 and 91 "Premium" fuels just have a higher ethanol content.

Just be sure to richen up the mixture when you switch to the e20-e30.

High timing isn't something I'd play with, you make more power with boost, same goes for rpm. General rule is to keep boost high and rpm/timing low as stated above.

11:1 is safe IMO. But you just have to let your setup tell you what it wants. As long as your plugs look good you could probably go leaner.

I've been running e30 in the talon for a bit now. I finally got a good 16g to replace this nearly blown 14b (burning oil, leaky exhaust housing, etc) so I'll be able to see how far E30 gets me on evo 560s and a walbro 255.

I get about 30ish miles or so less per tank on e30 than 93, but the e30 is much cheaper on a fill up.

I ran a good 30+psi through my e316g on e30 and methanol injection. Not sure I even needed the meth. Was a 10gph nozzle in the TB and 2 .75 pre-turbo.

http://www.dsmtuners.com/forums/nit...361565-pre-turbo-setup-dual-75gph-250psi.html

The engine eventually let go. I later found that it was rebuilt with no oil squirters/cast pistons and tight factory new spec ring gaps. I think this is what destroyed my engine not detonation. I had no knock up until the big bang.

See post #53...

http://www.dsmtuners.com/forums/tuning-engine-management/366625-tuning-e85-2.html

 

[T is for TURBO]

I don't know if I can get 93oct w/o ethanol. The only place that I know of that sells ethanol free gas only goes as high as 91oct better than 87 I guess...

So, If I were to get a good tune at 11:1 with 91oct at my desired boost. What would you suggest for timming (I understand I'm asking somthing that is subjective, as each setup is defferent) when switching to e20/e30? Would you suggest leaving the time untouched from stock? Or go the opposite and remove a bunch of timming?

Sorry, I'm pretty new to tuning, so bare with me... I'm confident I understand the theory of tuning, I just lack... well... practice. I'm just trying to make sure we are on the same page here.

My idea in the long run is to document the shit out of this. Get good logs, starting out with pump only then working up to E20, then E30, E40, and finally E50, or when ever I start running out of fuel.

-Shawn

 

[snooopy365]

A According to the pic below taken in Europe e30 is 95 octane. If that is so, a 1:1 ratio of e85 and e30 would be right at 100 octane and fairly easy to mix.

I'm pretty sure that isn't a picture taken in europe.

Normaly we use the metric system here, so there is no "gallon" its: liter here.
And the octan ratings doesn't match.
We use ROZ instand of MOZ so your 87octan is 91 octan here.
But most gas stations doesn't even sell 91 octan, it starts with 95.

So this picture is not from europe! In ROZ E85 would have something like 108+ octan.

 

[forcefed86]

I'm pretty sure that isn't a picture taken in europe.

Normaly we use the metric system here, so there is no "gallon" its: liter here.
And the octan ratings doesn't match.
We use ROZ instand of MOZ so your 87octan is 91 octan here.
But most gas stations doesn't even sell 91 octan, it starts with 95.

So this picture is not from europe! In ROZ E85 would have something like 108+ octan.

Sorry for that... the caption read

A “blender pump” in Britton, S.D., offers five blends of ethanol: E10, E20, E30, E40 and E85. Ethanol producers would like to see more of this. (Photo: American Coalition for Ethanol

I guess my brain associated Britton with Britain...

 

[Calan]

This is an interesting thread/subject.

The most important thing to remember with ethanol blends is that the octane rating is not a given. It seems obvious, but it's worth mentioning again: if you manually mix 90% pure 91 with 10% pure ethanol, you'll have a higher octane rating than 91 from the pump that has 10% ethanol in it (which is still 91 octane). The fuel suppliers target a certain octane rating and a certain percentage of ethanol, and use whatever grades of gas and ethanol they need to get there. So 91 pump with 10% ethanol is still 91 octane piss water....but it has ethanol so it takes more of it.

This is what pisses me off about the way ethanol fuels and blends are marketed; "ethanol blended fuels" and "gas with ethanol in it" are two different things, but they are presented (or at least assumed by most people) to be the same...which leads to much confusion.

But I digress. Back on topic...

It all comes down to a balance of knock suppression and how much fuel you can deliver. If you only need x amount of knock suppression and your local E30 can provide that, then you obviously can supply less fuel and still hit your target boost/hp numbers. If on the other hand you need more octane to suppress knock at your given boost/hp, then you'll need to run a higher octane ethanol blend and therefore supply more fuel.

My car will knock if a gnat farts on the hood, so I need all the octane I can get. But it would be nice to run fuel with less ethanol if I could get the same results, especially if it's cheaper coming out of the pump and requires less of it.

On a semi-related note, for those of you that run your own mix of ethanol and pure gas, here is a spreadsheet that will calculate percentages, octane rating, SG, etc. based on the number of gallons of each fuel type.

 

[snooopy365]

Sorry for that... the caption read



I guess my brain associated Britton with Britain...

No problem, just watched the picture and thought: Where can you buy fuel with an octane rating this damn low in europe
of course using different octan ratings + Britton does explain that

 

[T is for TURBO]

Calan, thanks for that info. I did not know that about the blends. I guess that's why it says "Up to 10%" rather than just giving an actual percentage.

Now just to clarify what you mean:

They take two fuels; gasoline and enthanol; then mix them together at what ever ratio (so long as it is 10% or under enthanol) to get a 91 octane fuel?

 

[Calan]

They take two fuels; gasoline and enthanol; then mix them together at what ever ratio (so long as it is 10% or under enthanol) to get a 91 octane fuel?

Correct.

I'm sure they all have their own standards as to what gas and ethanol they use, but there is very little regulation with it now from what I've seen. At least around here, stations were once required to mark any "gas" pumps that contained 5% or more ethanol; now they can go up to 10% without any marking at all. That is why we now have stations that proudly proclaim "No Ethanol!" on their pumps, to differentiate them from those that do contain that bad ole' ethanol.

Refineries do this because they can produce "gas" for a given octane rating cheaper if they blend in some ethanol (plus the EPA now places some mandates on them). Not only do they save money during production, but the vast majority of consumers aren't aware that it also takes more fuel with that 10% ethanol blended in, so the refineries also make more from increased usage. And common sense says that they wouldn't be using the best grade of ethanol to cut the fuel with either if it's done at the refinery.

But again...this isn't the same as true ethanol-blended FFV fuels. Although the difference should be clearly marked at the pumps, there is still a lot of confusion and it's an important point to remember. If you buy "E20" (or E30, E60, whatever) to get more octane, make sure you are paying for a 20% blend that really has more octane; not a 20% blend that is just watering down your gas.

For those of you with an account over on the ECMLink forums, I did a bunch of testing on various fuels a few years ago that is somewhat related to this, and found some interesting results. The thread can be found here.

 

[T is for TURBO]

Okay, now that I'm on the same page as you, how do you interperate this:

•E20 – a 91 octane grade fuel containing 20% ethanol and 80% gasoline. E20 is a higher fuel economy, lower cost fuel option for Flexible Fuel vehicles. It is not recommended at this time for use in other vehicles due to the lack of long term testing.

LINK

Would you say that their final product is 91 octane? or they start out with 91 octane and mix 20% ethanol?

The reason I ask is; these Renew stations are actualy blender pumps. When you pump your E20 or E85, the fuel is being blended from two seperate tanks. One enthanol, the other gasoline. The reason they do this, is becuase it makes the fuel cheaper for the consumer. There is a tax credit for every gallon of gas sold that is blended with ethanol. This way, since you are technically mix the two fuels at the pump, you get the tax credit via a cheaper price at the pump.

My interpretation is that the final product is a 91 grade. But how do they do that if the fuel is comming from two pumps? I would think that is would be tough to mix it with any kind of accuracy if an octane rating is the end goal, as opposed to just mixing 5:1 gas/ethanol.

Your right, this is confusing

 

[Calan]

My interpretation is that the final product is a 91 grade. But how do they do that if the fuel is comming from two pumps? I would think that is would be tough to mix it with any kind of accuracy if an octane rating is the end goal, as opposed to just mixing 5:1 gas/ethanol.

Your right, this is confusing

I agree with that interpretation.

The statement "a 91 octane grade fuel that contains..." sounds to me like exactly what it says; 91 octane. If it's truly a blender pump and 20% ethanol, then they are blending a lower grade of gasoline with it to arrive at a final octane rating of 91.

A perfect example of the point I was making.

 

[T is for TURBO]

Uh, I think I'm just going to go to one station you get pure 93 and mix it with E85 from another station...

 

[Calan]

Uh, I think I'm just going to go to one station you get pure 93 and mix it with E85 from another station...

Not a bad idea if you don't know what they are really pedaling; especially if you can find some E100 to do your home-blending with.

On a more positive note, you can rest assured that the octane rating will definitely go up as the amount of ethanol increases in these blended fuels, no matter how crappy the gas is that they mix it with. At higher concentrations of ethanol, there simply isn't enough gas to make a difference, no matter how low it's octane rating.

Using an octane rating of 113 for pure ethanol, several assumptions, and some very crude math...

A 10% mix of pure ethanol and 85 octane gas (about the crappiest grade of gasoline that most refineries would bother making I think) would probably have an octane rating somewhere around 88 or so. A 10% mix of ethanol and 87 octane would be around 90. A 20% blend of good ethanol and that same crappy 85 octane gas would be at the 91 octane mark, while a 30% blend would be something like 93. Extrapolating that out and running the most common numbers, we get this:

(pure ethanol with an 85 octane gasoline cut)

E10 = 87.8 octane
E20 = 90.6 octane
E30 = 93.4 octane
E40 = 96.2 octane
E60 = 101.8 octane
E85 = 108.8 octane

(pure ethanol with an 87 octane gasoline cut)

E10 = 89.6 octane
E20 = 92.2 octane
E30 = 94.8 octane
E40 = 97.4 octane
E60 = 102.6 octane
E85 = 109.1 octane

Like I said, this assumes a LOT such as octane rating method (RON/MON), that refineries/blenders are using pure ethanol, that there is such a thing as "pure" gasoline, etc. I'm also greatly simplifying things by ignoring ethanol's higher vapor pressure, effect on burn efficiency, etc. etc. etc. The true numbers would probably vary quite a bit (my guess is they would really be 2-3 points lower), but you get the idea. As a point of reference, 105 is commonly tossed around as the octane rating for E85; but considering E85 is sometimes really E70 or anything in between depending on the season and region, you can see how inaccurate this number can be. Not only that, there is also controversy about how the E85 octane rating is calculated in the first place!

Unless a blended fuel specifically states the octane rating, you can bet that the oil man has used the cheapest ethanol and gas available to create a blend percentage-based "flex fuel" that is as cost productive for them as possible. Since most FFV's will run all day on a low-octane fuel, a high octane rating isn't a priority....it's just a result.

To put it another way:

1. Gasoline is marketed and sold by octane rating, and usually contains some percentage of ethanol
2. FFV fuels (ethanol blends) are marketed and sold by ethanol percentage, and have some resulting octane rating

*****

To take this a step further using an example...

Lets assume that the lowest grade gasoline that a blender station has in it's tanks is 87 octane, and that they are using E100 for blending (which is almost pure ethanol but not quite, due to some additives to deter the local bootleggers. ).

It wouldn't make much sense for the station to maintain another tank of lower-grade gasoline used only for blending, so I think you could be relatively confident that the octane ratings for various unrated blends would fall somewhere around the numbers in my second list up there, minus a point or three. And based on that, E10 is out for us due to the octane rating alone, and the E20 probably wouldn't be worth messing around with unless it is much cheaper than the watered-down 91 pump piss that you can buy at any 7-11.

Personally, I would stick with E60 and above since you can be pretty sure of a decent octane rating (whatever it actually is) based solely on the blend percentage alone, even with crappy gasoline used as a cut....unless a specific octane rating is mentioned otherwise for the lower blends.

Keep in mind that this is all just based on my experience, a bit of research, a little common sense, and some 5th grade number crunching...so take it for what it's worth.

EDIT:

@ Shawn: Notice that Renew Fuel's statement "E20 – a 91 octane grade fuel containing 20% ethanol and 80% gasoline" falls right in line with an ethanol blend using 85 or 87 octane gasoline, depending on the margin of error in my numbers. Coincidence?

 

[forcefed86]

The problems with the race gas calculators is your going by octane numbers. E30 is estimated 93-95 octane. IMO it will suppress knock better than it's equivalent 93-95 octane std petrol fuels. Same with E85's 105 "rating". If your going to play with blends I think it would be a good idea to get an ethanol percentage meter on the return line. That way you know your content all the time. Keep it over say 50% and see how far ir takes you. The gauge is $185 and the sensors can be picked up on ebay for around 100.

Zeitronix ECA : SEMA Award Winning Ethanol Content Analyzer and Flex Fuel Sensor for E-85 and E-85/gasoline Blends

 

[Calan]

Or just carry around one of these for $16.

 

[forcefed86]

Or just carry around one of these for $16.

That's the one I have. They are great for testing seasonal blends of e85 if that is all you run. FYI you can also get a smaller one that reads down to 10% from Briggs and Stratton for 7.50.

http://www.smallenginesuppliers.com.../Briggs_Stratton_Small_Engine_Tools35122.html


Problem with the tube testers is not knowing the exact mix in the tank at all times. Esp if you're going to multiple stations and blending. I suppose you could install a petcock of some sort on the fuel rail and constantly test after each fill up. But it's not very practical. I'm always digging through the garbage cans at the gas stations looking for a water bottle to put a little fuel in to test... The things we do to go fast.

I believe those ethanol sensors are 0-5v ref. If you have a dsmlink or AEM etc you could probably figure it out with some simple math and vile tester.