TexasDude74

I'm having difficulty finding anyone with real world experiences building a dedicated E85 engine. Any idea what the max compression E85 could tolerate in a big block chevy would be? Reason being is that I have a AFR headed tall deck 610 with coated pistons and chambers, but the compression is 14:1. Anyone out there with an opinion on whether E85 would handle it?

xpndbl3

iTrader: (5)

should be fine with a big cam, but just check out the timing curve and back out if there's pinging. E85 likes a warmer motor as well.

wannafbody

iTrader: (1)

sorry to tap the tread, can you run E85 in any gas motor?

xpndbl3

iTrader: (5)

not unless you burn the prom for it on a efi motor. Or it's a newer flex fuel vehicle. There is no benefit unless you're running the extra compression to somewhat makeup for the more fuel needed.

Sonix

iTrader: (1)

Five7 kid runs E85 in his big block 396 car, at the track mostly.

I agree though, 14:1 is still a fair bit, you'll want a big cam to bleed some of that off.

5678TA

i've heard that E85 is max, 105 octane..

Sonix

iTrader: (1)

Yea, it's hard to base it's burning properties solely on octane rating though. Since it's an ethanol blend it has some properties akin to water, ie, when it vaporizes it cools a lot. It needs a warmer motor to properly vaporize, but the cooling effect also helps add to the "octane" value. etc etc. So it's hard to quantify.

TexasDude74

Yeah, all alcohols are supposed to cool the intake charge quite a bit more than gasoline does. Which is a real plus when it comes to preventing detonation. But, finding the true octane rating of E85 seems rather difficult at best. Online sources state its' octane is somewhere between 100 and 111, which is the highest number I've found. But, on some of the E85 websites I've been to they state 12:1 is about the highest compression ration E85 will support. I've seen a fair amount of 11:1 engines running on premium unleaded though, which is only 91-93 octane. So I would think E85 would have to be good up to at least 13:1 wouldn't it??? Even if it's only truly a 100 octane fuel.

rx7speed

it's really all in how it is built. if you knew your tuning you could get prem gas to run on 12-13:1 compression without detonation. again if you know what you are doing. and yet I have had cars that would ping like hell even using 8:1 compression unless I retarded the timingso far back that it would hardly idle.

five7kid

iTrader: (14)

Member IHI has done a lot more research and is building an engine for it. Check out the E85 thread on the Carb forum, starting about post #99.

IROCFAST

iTrader: (3)

Way old thread, but read this...Ohio Crank has it in a 15:1 555 and it is working fine.

http://www.yellowbullet.com/forum/sh...ad.php?t=88332

kens86

my buddys 13.5-1 412ci is running it all year with no problems, and it's pretty consistent.

FRMULA88

My engine knocked itself to death TWICE..

13:1 compression.. big cam, yadda, yadda, yadda

The culprit was insufficient octane of the fuel.

DO YOUR HOMEWORK I wish did, because E85 is not truly 105 octane.

The RON is high (105) but the Mon is very low... (90)

R+M /2 is really 94-96 octane for pump grade

98-99 for race grade VP or Sunoco.


I can show you pictures of the so called "cooling affect" on my pistons.

What a bunch of hype, the truth is out there... so plan accordingly, If I only spare 1 person the frustration and expense I have been thru it was worth posting this:

http://en.wikipedia.org/wiki/E85 see chapter 5..

http://ethanolrfa.3cdn.net/dd9e74ce1..._rbm6bdgh3.pdf

See Chapter 1 pages 3 & 4 esp. figure 1-3 also chapter 5 page 29

http://www.racegas.com/article/11


If I had to do it over the most I would have ever planned for is 11:1 static compression based on the "real word" octane values of E85, & not the hype in the car magazines.. if you read these articles most of them never exceed this 11:1 limit... IRONIC ?!

I am going to switch to 112 race gas, which was the original plan for this build.

FRMULA88

VP relies on MON numbers because the MON test more accurately simulates racing conditions. Don't be fooled by high RON or R+M/2 numbers. Many companies use these simply because they look higher and are easier to come by because of the test methods. Also bear in mind that the ability of fuel to resist detonation is more than just a function of octane


http://www.vpracingfuels.com/index.h...estion&ID=1981




The following is a comparison of the two machines used for testing octane numbers:
Motor Octane Machine Research Octane Machine
RPM 900 600
INTAKE TEMP. 300 DEGREES F 120 DEGREES F
TIMING VARIABLE BASIC FIXED AT 13 DEGREES
(DOES NOT CHANGE)
SETTING 26 DEGREES

As you can see, the Motor Octane machine runs at a higher RPM, higher temperature and more timing. This machine puts more stress on the fuel than a Research machine and more accurately simulates a racing engine. VP Racing Fuels always includes Motor Octane Numbers when promoting its fuels because our fuels are used exclusively for racing applications.

The Research Octane machine will always produce a higher number for the obvious reason that it does not put the same amount of stress on the fuel. This number is used by some fuel companies to trick the racer into thinking the fuel is rated higher, i.e., higher quality, than it really is. The “R+M/2” Octane Number is the average of the Research and Motor Octane numbers for a fuel and is the number displayed with yellow labels on retail level gas pumps.

When comparing fuels for racing purposes make sure to compare Motor Octane Numbers because these are the ones that count in your racing application. Focusing on the MON of each fuel will help ensure you’re comparing apples to apples with regard to octane.

http://www.vpracingfuels.com/index.h...estion&ID=1980

FRMULA88

I read this and wept.... check on the MON number for "Race Grade" C85

http://www.vpracingfuels.com/master-fuels-table


Sunoco's is about the same, but bit more MON.

http://www.racegas.com/fuel/18


Anyone who thinks the stuff at the pump is better than these products is delusional.

There is no way an engine with more than 11:1 compression can safely run on this.

PLAN YOUR BUILD ACCORDINGLY

Orr89RocZ

iTrader: (20)

I would disagree. I have seen a few over 11 to 1 on e85. Hell i have run 11:1 on straight 93 oct sunoco fuels.

Max limit however is so dependent on so many other variables you cant put a number on it. There are guys on chevelles.com, which is a good site for big block information, claiming to run E85 and other Exx alcohol fuels at near 17:1 comp. i have my doubts but again its very hard to say without knowing entire combination

FRMULA88

Exactly, I have my doubts also, because anything past 15:1 has to deal with the law of diminishing returns..

All I am trying to say is based on real world data... E85 does not work in my application, and actually caused the detonation which damaged the pistons.

Orr89RocZ

iTrader: (20)

Fuel doesnt cause detonation. Its spark timing and gas mixture that will influence that, among the rest of the engine combination. If you played with air fuel ratios and backed off timing and had correct heat range plug in the motor, and if it still had detonation, then ok maybe there isnt enough octane. But by itself, the fuel doesnt cause the problems, its the other parts of the combination and tune up. You never know what you are getting into with e85 blends and frankly any pump gasoline. Not all stations have same quality fuel. I know engine builders on another forum who claimed to have tried 17 different pump gas stations til he found max power for a specific race class. Thats insane but shows there are variances. Anytime you push limits of compression you will need to do experimenting to determine if its safe or not. More time and money

FRMULA88

INCORRECT... octane rating is a fuel's resistance to detonation. period.

The higher the octane number the more resistant it is. use regular 87 in a carbed engine built to run on 93 and you will detonate... timing, etc. will help but without a knock sensor or a computer to make the ajustments you are in trouble...

Orr89RocZ

iTrader: (20)

Resistant is the key word. The fuel by itself doesnt cause detonation. If your motor is not designed to operate at 93 octane, then dont run 93 octane. The engine combination determines fuel required and whether or not it detonates.

You can make any motor detonate on any fuel, its not the fuels fault. I can throw a hot plug in a motor that needs a cold plug and get it to preignite on same fuel, or even detonate because plug didnt pull enough heat from chamber. Understand what i am saying? Just the way you stated that e85 caused your motor to detonate bothered me, i am not sure you meant that way or just meant to say for my particular example e85 was not enough.

I think we understand the point its just semantics and wording that i took in the wrong way?

Orr89RocZ

iTrader: (20)

Let me clarify what i was getting at here. This statement bothered me because cylinder pressure is not determined solely on static comp ratio. So you cant really make a blanket statement like that because some may some may not run at that comp

At 13:1 yours would be the upper limit and possibly exceed e85 capability.

Idk maybe i am too picky on wording today and just misunderstood

jermdm

I think E85 is overrated. I don't see any gain in using it, atleast in street use. I work for a ford dealership and flex fuel vehicles are common. E85 will make your engine run lean. The PCM will compensate for the lean condition and inject more fuel. We see a lot of check engine lights when customers use it. Even though E85 is cheaper at the pump, you'll probably spend more money on E85 since you're injecting more fuel compared to regular gas. Another thing to consider is E85 is corrosive and the factorys use stainless steel fuel lines so it wont eat thru the lines and the O-rings on the injectors and fuel lines are a different material than normal since E85 will eat those too.

Orr89RocZ

iTrader: (20)

If you have a flex fuel vehicle you can run e85 no issues. Atleast the fueling part. All the components should be compatible and ecm has compensation tables to allow for proper fueling.

Last i heard however e85 is being phased out. Just costs too make it for little return. The industry is moving towards e15 which is not a good thing from all the people i have seen speak about it. The chemistry isnt good because of how easy gas and alcohol can separate and how water can easily form in the gas tank. I'd have to find the link again explaining it better than i could ever try

T/Aperformance

You are right it would actually cost you more to use E85 from the oil company compared to unleaded fuel, The oil company sells E85 for a bit less than unleaded fuel but not low enough to make it be worth using,
Usually people who decide to use it is after the have bean using unleaded fuel and the the E85 cleans out the fuel lines and pushes all the varnish from the unleaded fuel into the injectors and clogging them or disturbing the spray pattern.

I won't even get into the octane rating of E85, but it is higher than premium unleaded And closer to race gas, And for my car I won't use any of them I run E95 I would like to run straight ethanol but the law says I must poison
I would like to see A few turbo guys run it and see just how much boost they can get, since E85 or better ethanol blend burn much cooler race fuel or unleaded fuel.

FRMULA88

Unless you have built one to run successfully on E85 I would consider keeping
comments to oneself. If you have then PM please me the details..


Most replies are "this guy I know did it..."

Well ,guess what ,THIS GUY actually tried to do it and it does not work for this combination... i

If the fuel really is 105 octane it would not cause this type of damage.
we were rich mixture, conservative with timing, etc, etc... but you can't expect a product with a reall world octane of 94-99 to do the job that is meant for 110-112 race fuel..

This damage is text book DETONATION. The detonation was due to insufficient octane.

Plan your build accordingly do your homework and don't ASSUME anything.

FRMULA88

2nd time around.... this time on "RACE GRADE" VP C85 fuel

More of the same.

2 strikes is enough for me..

Keep in mind an engine dyno will not load the the engine like a chassis dyno a dragstrip pass..

This stuff worked just fine on the engine dyno... because not loading the engine.
this is the 108 RON of C85...


installed in the car... with a real load,, it was done
this is due the 90 MON of C85..(too low)


VPs 110 race Gas the MON is 107.... 17 points more than E85.

These are simple facts... and E85 is not enough for this combo..

FRMULA88

In total 4 piston damaged.

#8 the worst

#6 deformed at the valve relief (look at the picture) see it's not round @ 10 o'clock position.

#5 & #7 top land erosion


looking at the cylinder heads you see those shiny speckles on the face of the valves.... that is piston material.

Text book detonation.

bye bye E85...

FRMULA88

Which is why if were going to build a E85 motor we would treat is as a "pump gas" build with not more than 11:1 static compression.

My 383 ran perfect for 12 years on premium (93 octane) 10.5:1
hundreds of dragstrip passes and never a problem.. but that build was based on "pump gas".


This new motor was built based on using 110 race gas, Our mistake was assuming E85 has similar properties... IT DOES NOT. Had we known the facts the build would have been done differently to run on E85.

We are sticking to the original plan and going to run on Race Gas.

FRMULA88

In other words build your engine based on the fuel you plan to use...

I am sure we could safely run E85 if we changed the cam... lowered the static compresssion.. etc...etc but then we would be making less power versus using the fuel this engine was actually designed for.

other than new pistons and bearings the only other expense is converting the CARB from E85 back to Gas.

Orr89RocZ

iTrader: (20)

Hows a stock bottom 10.0:1 ls2 with ported heads and cam on e85 plus meth inj make 816 whp on only 11 psi on mustang dyno thru a trucks 14 bolt rear. Its pretty powerful stuff when used right

Another local vette picked up 15 whp on a n/a combo, over a straight pump gas tune. Its higher octane allowed few degrees of timing to make the power

FRMULA88

you see what I mean it's always "some other guy" what does your E85 motor do?

Orr89RocZ

iTrader: (20)

These are close friends of mine, a guy who tunes LS cars for side money and has done many. That LS2 was his personal truck which I've been in. What more do you want? I dont run E85 because we dont have it around here but one station 30 min away.


And do you work for the government or a gasoline company? LOL whats your personal vendetta against E85? Just because you arent smart enough to make it work for you doesnt mean you have to trash everyone else who does use it with success. talk about narrow minded

FRMULA88

Yup all close friends,,, and they all have access to E85 except you for you that is. those friends must live aweful far away from you

Good for them.

I am sure with the right application is it just fine but to assume you can fill er up @ 3.29 gallon and expect it to out perform True race gas is pretty far-fetched,,,


You believe who you want and do what you want with your build...
I am done playing with this wanna be race fuel.

You can also keep your comments about my intellect to yourself... I don't know you and with a attitude like that I don't care to.

buh bye !

T/Aperformance

Who is this comment for?
And is it the fuels fault if the engine was built and tuned for a higher octane rating than the fuel that was used?
Was it the fuels fault for someone not doing there home work before hand?
Now my motor was not built to run E85 or better fuels, It can run on premium unleaded fuels, I am using basic but new fuel injectors 24lbs, I changed my fuel lines to stainless steel line, new FPR and a new fuel pump for use of ethanol. I did my home work before I started, And I'm still learning things like tuning my computer to run my engine perfectly, My car runs much cooler on ethanol, Yes I use more fuel than I would if I ran gasoline, I run E95 fuel, E85 from the local gas station is not really cost effective at this time,
Now if you used E95 or straight ethanol in the engine you are showing with the damage you would not of had that happen.
Its kind of bad for someone to blame the fuel for there problem when it was really the fault of the builder and not doing there home work before starting.

T/Aperformance

That is very impressive, Was meth really needed to get those #?
And I can see the vette picking up that much,
Don't you wonder what your car would do on E85 or better fuel?

And yes I am an advocate of running ethanol fuels, I don't like people who give miss information on it, For those who want to know I started using ethanol because I'm cheep, not to save the planet. I learned how to make my own fuel, Applied for and received my license for free to make up to 10,000 gallons of ethanol based fuel per year, And it cost me about $1.45 per gallon if I use corn. I run it in my daily driver, My Trans Am, and my lawn equipment.

FRMULA88

I never blamed the fuel,,, I just merely dis-spelling the misinformation that was used which led to my problem... Please RE-READ my posts and you will understand that our problem was in fact mis-information. Has we known the practical limitations of the fuel our build would have been approached differently. In our case it simpy does not have the octane needed to run in this engine...

YET all these wanna-be's say it's 105 its 112...you can run up 15:1 because my brother's uncle's cousin's sister did it her car with 30 # of boost. it is simply not true.

Orr89RocZ

iTrader: (20)

Hey you started it by making comments about "its always somebody elses motor. Whats does your e85 motor do". Dont dish attitude to me if you cant take it back at you lol. I have no problem with you

Comments like that insult my actual posted data as if it was false and i was making things up. Then you come here to bad talk e85 because you had one motor that didnt like it. Sorry to hear but one bad example doesnt ruin the fuel

And yes close friends who have run it because they live in pittsburgh alot closer to the only 2-3 stations that sells it. I am not traveling 30 min to pick up gas when i have 3 stations of good 93 oct within 2 minutes.
And no i am not filling up a drum. I have 110 oct available also up the street and other race gas 15 min away at the track i can buy and fill a drum if needed, e85 makes no sense for me in my current area.

I cant say for sure but i know the engine was limited in injector size. Truck wouldnt make the power on injector alone, the meth nozzle provided the extra fuel. I have no doubt good numbers could be made on e85 alone for boosted builds like this. Problem is at hp levels that high you need huge injectors which arent readily available for stock ecm drivers. Would need low impedence drivers. Now they do make bosch 160 lbs and i think injector dynamics 2000cc's. they may support big e85 power.

Let me put that in perspective. My 401" afr 195 head twin t60 combo did 640 whp on this dyno at 12.5 psi but thru a stallled th400. A local guys big block 496 with twin t70's and a t56 made 809 at 10 psi. A cam head ls2 made 816 on e85/meth
mix thru a t56 on 11 psi. thats an incredible amount of hp per pound boost, matching or exceeding engines of much larger size.

I wont run e85 becAuse i am not set up for it and its just not readily available in my part of town. Not too many stations in pittsburgh carrying it. I'd rather run gas and meth mix as it seems to do better. My local shop friend has a 5th gen whipple charged camaro ss. Did an experiment on c16 race gas vs pump 93 and loads of methanol. Car didnt do any better on c16! It was an eye opening dyno test. Methanol charge cooling was worth more than octane increase alone by the race gas.

AJ_92RS

From what I've read, ethanol doesn't have to meet the same ratings as gasoline. The "E85" simply states the content of ethanol can be as high as 85%, but that doesn't mean it's going to be. Just as E10 is "up to" 10% ethanol, but isn't supposed to go any higher.

Taken from this literature:
http://ethanolrfa.3cdn.net/4eea401b7..._nrm6bhv0i.pdf

With nearly a 10% variable, determining an accurate octane number is nearly impossible without a 10% variable.

It's safe to say, a wise choice would be to assume the average to be on the lower end of the variable and build the engine accordingly.

Fast355

iTrader: (2)

Someone is just mad because he did not tune his engine correctly for E-85. I saw a 14 ft/lbs and 13 rwhp gain on a Mustang dyno with a good E-85 tune on my Flex Fuel 2012 Nissan Titan. On 93 octane E10 I have knock retard under load before I get to MBT. On E85 I can reach MBT and it made a nice power difference.

I went from 296 RWHP and 388 RWTQ to 309 RWHP and 402 RWTQ on a Mustang dyno and it was 15°F hotter in the shop during the E85 runs.

I pickup 2-3 tenths in the 1/8 running it.

Orr89RocZ

iTrader: (20)

Thats pretty neat. I have a flex fuel sierra 6.2L that picked up 22whp on a dyno tune on 93. Bone stock nothing done to it. 330 whp all tuned. I have not tried E85 as stated, gas stations are rather far away and frankly i dont care enough about what my winter driver does for power, as its no race truck. I just had it tuned because i am good friends with the local shop and tuner. I understand the octane and cooling benefits could lead to more power in the right combination and this motor may be an example. Its already a decent compression motor in a very heavy vehicle, so loaded down this motor wont take alot of timing. E85 could help with that, just not worth the effort and cost in the end. It only gets 13-14 mpg as it is daily driving, e85 will be worse

five7kid

iTrader: (14)

I'll say upfront that I don't know Mr. FRMULA88 from Adam. All my conclusions are from what I'm reading here.

Cooling effect - apparently you don't read your own links. Cooling has to do with the incoming fuel/air mixture, not the piston temp. Vaporization is a cooling event (simple physics). It takes heat to change the phase of the fuel from liquid to vapor (that's how air conditioners and swap coolers work). The higher the heat of vaporization, the more heat it takes to vaporize the fuel. Ethanol has a higher heat of vaporization than gasoline. During hot summer months at the track, I could put my hand on the intake runners with the engine idling and the intake would feel cold. With gasoline, my challenge at the track would be getting the engine cool enough between rounds. With E85, more often the challenge was keeping the engine warm enough. An "air gap" type intake may not be the best thing with E85. Power adder guys, particularly turbos from what I've seen, like E85 because of its ability to suck up heat. But, if you don't fully vaporize the fuel prior to ignition, you will have a lean condition (assuming the mixture is correct if fully vaporized). A lean mixture is more prone to detonation.

There is a lot more to detonation than fuel octane, as Orr is trying to communicate. Sure looks like you addressed only one aspect, and are going off on the fuel rather than looking at all aspects of your build and tune. What I have said elsewhere regarding using E85 is that 12:1 is typically do-able with a decent tune. If you go higher than that, then you'd better watch your tune very carefully.

Personally, I quit running pump E85 because, as stated, it doesn't have to be 85% ethanol. In our area, it typically drops to 70% during the winter months to help flex fuel vehicles start easier in the cold. It takes awhile for their tanks to deplete and replenish to 85%, and the racing season starts long before that. Since the volume of E85 needed for a proper mixture is different than for E70, and little things like emulsion bleeds change between gasoline and E85, that variable was making keeping a tune very hard. The track here sells E85, and it was very consistent (and the quality of the 15% gasoline was probably better than at the pumps). When I started using track E85 exclusively in the middle of the 2008 season, the car became very consistent (I'll show you a pic of the trophies earned in 2009 if you like).

Also, personally, I didn't have any issue with detonation because I was only running about 10.5:1 CR. I kept thinking about raising it to take better advantage of the E85, but good parts for 396 BBCs are not readily available. Then I started an LS build for the car, so it's all moot for me now (I'm sticking with pump gas for the new build).

FRMULA88

LOL 10.5:1 that is not 13:1

Why are you comparing apples to oranges?

Based on my personal experience you don't want to exceed 11:1 to be safe with E85, because it is not 105-112 octane like everyone seems to think.
I was initially led to believe this as well which is why we ran it in a 13:1 engine.

In reality it is only 94-99 at best. I am glad we sorted thru all the BS about this fuel because in fact that was the source of the issue. We did not do our homework and has this problem, but I am certainly not going to de-tune this motor just to run this fuel...


If you like it so much why are switching back to gas?

It's obvious none of you can read engrish...

bjankuski

For the last 5 years I have been running a 555 BBC on E85 with 13.5 to 1 compression and I have had no issues. I bracket race this car every weekend and the car is .1 tenth faster with E85 then race gas and that is on a car that runs mid 8's. I buy my E85 from the local gas station and I do only buy it when it is the summer blend E85. I store up 55 gallon of E85 for the next year so I can get through the spring when E85 is actually only E70 or E78.

In my opinion E85 works fine in a 13.5 to 1 compression BBC.

tittan1500

Just chiming in on a old thread - Real world experience

I run E85 on a 14.5 comp 632 bbc that makes 938hp at the tire.
So far on the second summer and the motor runs cooler and is much easier on the wallet than C16.

Not my friends buddies car or my uncles car - My personal experience

E85 FTW

big hammer

Ethanol is also loaded with oxygen so there is some small gains to be had even with a stock NA engine. But it has to be tuned for it.

hpmustangs

i know this thread is really starting to get old but im looking at building a 3.4 with all stock parts essentially maybe a couple small extras but this will be a bone yard build all day and i seen if i mix and match i will end up calculated around 13 to 1. my goal has always been to just build a mild engine for e85 not for power but for fuel millage kinda as a proof of concept that utilizing the octane o2 and cooling affects of e85 on a stockish build maybe help her breath a little bit but no real power adders as a stock 3.4 has enough power for a comuter s10 5 speed. what thoughts do you all have on the engines ability to not self destruct or should i try some mods to back the compression off a tad