E85 Questions: Is it right for me?
Rotary for life!
Joined: Oct 2005
Posts: 1,155
Likes: 1
From: Somewhere...
I definitely recommend E85 if your FD is a weekend car depending on the availability.
My experience so far:
- Hard to start on cold starts but does start first time (few gun shots
)
- You NEED to premix - E85 is very dry and will damage your seals if not premixed
- Fuel efficiency is out the door - I have 4x 2000cc injectors for flow
- Injectors definitely should be upgraded along with your fuel filter
- Great power capability with little concern of detonation
- Fuel lines have to be replaced
- Smell - I like it but depends on the person
- You may need to plan your trips depending on availability
My FD is a weekend car and I would not go back to Petrol after seeing the potential that E85 has in terms of performance and reduced detonation.
My experience so far:
- Hard to start on cold starts but does start first time (few gun shots
)- You NEED to premix - E85 is very dry and will damage your seals if not premixed
- Fuel efficiency is out the door - I have 4x 2000cc injectors for flow
- Injectors definitely should be upgraded along with your fuel filter
- Great power capability with little concern of detonation
- Fuel lines have to be replaced
- Smell - I like it but depends on the person
- You may need to plan your trips depending on availability
My FD is a weekend car and I would not go back to Petrol after seeing the potential that E85 has in terms of performance and reduced detonation.
I definitely recommend E85 if your FD is a weekend car depending on the availability.
My experience so far:
- Hard to start on cold starts but does start first time (few gun shots )
- You NEED to premix - E85 is very dry and will damage your seals if not premixed
- Fuel efficiency is out the door - I have 4x 2000cc injectors for flow
- Injectors definitely should be upgraded along with your fuel filter
- Great power capability with little concern of detonation
- Fuel lines have to be replaced
- Smell - I like it but depends on the person
- You may need to plan your trips depending on availability
My FD is a weekend car and I would not go back to Petrol after seeing the potential that E85 has in terms of performance and reduced detonation.
My experience so far:
- Hard to start on cold starts but does start first time (few gun shots
)- You NEED to premix - E85 is very dry and will damage your seals if not premixed
- Fuel efficiency is out the door - I have 4x 2000cc injectors for flow
- Injectors definitely should be upgraded along with your fuel filter
- Great power capability with little concern of detonation
- Fuel lines have to be replaced
- Smell - I like it but depends on the person
- You may need to plan your trips depending on availability
My FD is a weekend car and I would not go back to Petrol after seeing the potential that E85 has in terms of performance and reduced detonation.
Thread Starter
Joined: May 2005
Posts: 1,012
Likes: 45
From: North Dallas, TX
Not sure if some of you guys understand.....if you have the FlexFuel sensor you can run E85 OR pump gas and the ECU will simply adjust the map to suit what is in the tank. No need to plan trips since you don't HAVE to run E85. If your tank is 93 the car will select the 93 tune all on it's own. If the tank is E85 it will run the high boost map. If it's a mix (E50 or whatever), it will shoot for a map that's somewhere in between.
At least that's how I understand it.
At least that's how I understand it.
10-8-10-8
Joined: Jan 2012
Posts: 848
Likes: 12
From: Australia
I have to go with Fuhnortoner on this.
I tend to think water injection is my preference, because (admittedly not knowing much about E85) I've heard bad things about E85 not mixing well with the oil injection system, and deposits forming in the ports. I haven't had anyone allay those concerns for me, so I just stay right away from E85.
I've also been told anecdotally (not sure if this is correct) that to make the same power level as normal gasoline, you need to consume more E85 as it has a lower BTU energy yield than gasoline. That gives rise to a thought- the car is going to be really thirsty just to make the same amount of power, which wouldn't be a win in my book.
Yes I've also heard it lowers detonation risk, but that isn't enough to sway me from all its other possible potential issues.
None of my opinion matters anyways (and you shouldn't listen to me), as we don't have much E85 or ethanol based fuels where I am in Australia, so I have very little exposure to the stuff, only what is told to me and what I read.
I tend to think water injection is my preference, because (admittedly not knowing much about E85) I've heard bad things about E85 not mixing well with the oil injection system, and deposits forming in the ports. I haven't had anyone allay those concerns for me, so I just stay right away from E85.
I've also been told anecdotally (not sure if this is correct) that to make the same power level as normal gasoline, you need to consume more E85 as it has a lower BTU energy yield than gasoline. That gives rise to a thought- the car is going to be really thirsty just to make the same amount of power, which wouldn't be a win in my book.
Yes I've also heard it lowers detonation risk, but that isn't enough to sway me from all its other possible potential issues.
None of my opinion matters anyways (and you shouldn't listen to me), as we don't have much E85 or ethanol based fuels where I am in Australia, so I have very little exposure to the stuff, only what is told to me and what I read.
Full Member
Joined: Sep 2004
Posts: 231
Likes: 25
From: France
My main concern for E85 is about what happens when E85 mixes with water => acid => corrosion.
My previous car was running E85 (RB26 S13 with big single), but I was using it everyday, so no risk of acid buildup.
Now with the FD, I usualy stop using it for 10 consecutive days and more. In western Europe, it's frequently cold and with lot of humidity in the morning, and I'm lot worried about risk of corrosion for my plates/housings/rotors... I love my FD too much.
That's why I didin't went E85. But I really would love to.
All I hope is beeing wrong about that and switching to E85.
My previous car was running E85 (RB26 S13 with big single), but I was using it everyday, so no risk of acid buildup.
Now with the FD, I usualy stop using it for 10 consecutive days and more. In western Europe, it's frequently cold and with lot of humidity in the morning, and I'm lot worried about risk of corrosion for my plates/housings/rotors... I love my FD too much.
That's why I didin't went E85. But I really would love to.
All I hope is beeing wrong about that and switching to E85.
Thread Starter
Joined: May 2005
Posts: 1,012
Likes: 45
From: North Dallas, TX
How does running E85 play into emissions testing? On the one hand, it's not stock so I'd think you'd fail emissions. On the other hand, E85 is mostly ethanol and would largely be producing CO2 and water vapor out of the exhaust pipe....wouldn't that be a plus for emissions?
I've been experimenting with E50 on my turbo Renesis , the main reason for going with it (vs E85)was that it offers better mileage for a street car while maintaining most of the benefits.
Have never seen any mention of it on this forum , just wondered if it was worth considering for you guys ?
Have never seen any mention of it on this forum , just wondered if it was worth considering for you guys ?
Not sure if some of you guys understand.....if you have the FlexFuel sensor you can run E85 OR pump gas and the ECU will simply adjust the map to suit what is in the tank. No need to plan trips since you don't HAVE to run E85. If your tank is 93 the car will select the 93 tune all on it's own. If the tank is E85 it will run the high boost map. If it's a mix (E50 or whatever), it will shoot for a map that's somewhere in between.
At least that's how I understand it.
At least that's how I understand it.
It can be as simple as fully tuning it on E85 and making a quick "ok, it's not going to blow up and driveability is tolerable" judgment on E50 and E10. Or it can be much more involved.
How does running E85 play into emissions testing? On the one hand, it's not stock so I'd think you'd fail emissions. On the other hand, E85 is mostly ethanol and would largely be producing CO2 and water vapor out of the exhaust pipe....wouldn't that be a plus for emissions?
As you may have seen in another recent thread I posted, I'm trying to determine what size turbo I'll end up with. As a result of my endeavors, I've realized that pump gas simply won't support my power goals. I'm not looking for insane power levels, but I'm really just not wanting to have to worry about where my next tank of race gas is coming from. Not only that, but 93 octane isn't always 93 so tuning on the edge isn't realistic these days. End game? I want to make a reliable 400whp and have a meaty power band down low with the EFR-7670 turbo.
*Enter E85*
I'm under the impression I'll be able to make significantly more power on E85. I live in Dallas and have quite a few E85 stations near my house so finding it is not that big of an issue. I know I'll need about 30% more fuel delivery and I THINK I'm prepared. I have the Rotary Performance fuel pump, stock primaries, and 2200cc secondaries. I believe I'll need an Adaptronic ECU with a Flex Fuel sensor and new fuel lines. What else am I missing? Is it that simple? And if E85 isn't available, does the ECU just revert to a 93 pump gas tune on the fly?
Questions
1) Is my injector and fuel pump setup sufficient for my power goal of 400whp?
2) Can the Adaptronic ECU be set to recognize whether 93, E85, or a hybrid mix of the two is in the tank? And if it can, does it have the ability to automatically adjust the tune to meet the available fuel's capability?
3) New fuel lines that are E85 safe....what else?
4) Is premix required?
5) Why aren't more people running E85? Seems like a great way to break the pump gas HP barrier. I'm guessing because it's hard to find?
As always, if anyone has a good link where I can do some reading that would be stellar. I've been able to find individual threads with bits and pieces of knowledge but I haven't seen an official E85 thread with verifiable info.
*Enter E85*
I'm under the impression I'll be able to make significantly more power on E85. I live in Dallas and have quite a few E85 stations near my house so finding it is not that big of an issue. I know I'll need about 30% more fuel delivery and I THINK I'm prepared. I have the Rotary Performance fuel pump, stock primaries, and 2200cc secondaries. I believe I'll need an Adaptronic ECU with a Flex Fuel sensor and new fuel lines. What else am I missing? Is it that simple? And if E85 isn't available, does the ECU just revert to a 93 pump gas tune on the fly?
Questions
1) Is my injector and fuel pump setup sufficient for my power goal of 400whp?
2) Can the Adaptronic ECU be set to recognize whether 93, E85, or a hybrid mix of the two is in the tank? And if it can, does it have the ability to automatically adjust the tune to meet the available fuel's capability?
3) New fuel lines that are E85 safe....what else?
4) Is premix required?
5) Why aren't more people running E85? Seems like a great way to break the pump gas HP barrier. I'm guessing because it's hard to find?
As always, if anyone has a good link where I can do some reading that would be stellar. I've been able to find individual threads with bits and pieces of knowledge but I haven't seen an official E85 thread with verifiable info.
Get an 8374 and run water injection. </discussion>
Thread Starter
Joined: May 2005
Posts: 1,012
Likes: 45
From: North Dallas, TX
https://www.rx7club.com/single-turbo...sults-1102073/
https://www.rx7club.com/single-turbo...sults-1070794/
https://www.rx7club.com/single-turbo...sults-1060852/
https://www.rx7club.com/single-turbo...-5psi-1103142/
https://www.rx7club.com/single-turbo...19psi-1102573/
auxiliary injection:
https://www.rx7club.com/3rd-generati...fd-fix-806104/
A really crazy dude with WI(YMMV):
https://www.rx7club.com/auxiliary-in...ection-863250/
Foolly sick 7670 build, shooting for low 300's
https://www.rx7club.com/build-thread...-more-1102781/
The 7670 crowd are pushing 20+psi to get 400's. More stress on the package to do so.
The 8374 bunch is hitting 500's in the 20's. Should be able to get 400's at a reasonable boost level.
At that point, WI is just a safety net. Knock reducer.
No one with the 8374 is complaining about spool.
If 400's are really your goal, the 8374 is a no brainer.
e85 conversion isn't insurmountable by any stretch, but sure gives some people headaches around here.
It's definitely harder than not attempting the e85 conversion in the first place. Esp if it's overkill.
Thread Starter
Joined: May 2005
Posts: 1,012
Likes: 45
From: North Dallas, TX
Excellent post. I've seen/read most of the dyno and build threads you linked but I'd yet to read Howard Coleman's "Making the case for the Rotary" thread. Very interesting. I need to read the whole thread but at this point, the first post at least has me intrigued.
How often do you have to fill the meth/water tank? What type of miles per gallon or fill up increment does it on average?
How often do you have to fill the meth/water tank? What type of miles per gallon or fill up increment does it on average?
corollary results:
https://www.rx7club.com/single-turbo...sults-1102073/
https://www.rx7club.com/single-turbo...sults-1070794/
https://www.rx7club.com/single-turbo...sults-1060852/
https://www.rx7club.com/single-turbo...-5psi-1103142/
https://www.rx7club.com/single-turbo...19psi-1102573/
auxiliary injection:
https://www.rx7club.com/3rd-generati...fd-fix-806104/
A really crazy dude with WI(YMMV):
https://www.rx7club.com/auxiliary-in...ection-863250/
Foolly sick 7670 build, shooting for low 300's
https://www.rx7club.com/build-thread...-more-1102781/
The 7670 crowd are pushing 20+psi to get 400's. More stress on the package to do so.
The 8374 bunch is hitting 500's in the 20's. Should be able to get 400's at a reasonable boost level.
At that point, WI is just a safety net. Knock reducer.
No one with the 8374 is complaining about spool.
If 400's are really your goal, the 8374 is a no brainer.
e85 conversion isn't insurmountable by any stretch, but sure gives some people headaches around here.
It's definitely harder than not attempting the e85 conversion in the first place. Esp if it's overkill.
https://www.rx7club.com/single-turbo...sults-1102073/
https://www.rx7club.com/single-turbo...sults-1070794/
https://www.rx7club.com/single-turbo...sults-1060852/
https://www.rx7club.com/single-turbo...-5psi-1103142/
https://www.rx7club.com/single-turbo...19psi-1102573/
auxiliary injection:
https://www.rx7club.com/3rd-generati...fd-fix-806104/
A really crazy dude with WI(YMMV):
https://www.rx7club.com/auxiliary-in...ection-863250/
Foolly sick 7670 build, shooting for low 300's
https://www.rx7club.com/build-thread...-more-1102781/
The 7670 crowd are pushing 20+psi to get 400's. More stress on the package to do so.
The 8374 bunch is hitting 500's in the 20's. Should be able to get 400's at a reasonable boost level.
At that point, WI is just a safety net. Knock reducer.
No one with the 8374 is complaining about spool.
If 400's are really your goal, the 8374 is a no brainer.
e85 conversion isn't insurmountable by any stretch, but sure gives some people headaches around here.
It's definitely harder than not attempting the e85 conversion in the first place. Esp if it's overkill.
if the goal is 400, and the turbo tops out of 420. and you can run e85 and use 25 psi to get to 400. then why not do so. power out of the engine is power out of the engine, it doesnt stress it any more then making 400hp from 18 psi from the 8374..
if he had the goal, or was opening to jumping into the 500hp 550hp range, then go ahead, but thats usually a whole next level of fuel pump setup, clutch setup, ect..
using the 7670 for a solid street 400 sounds like the no brainer, it makes it's fat torque at 3000 rpm. yeah it gives up flow up top sooner, but you don.t need all that on the street. remember the eng goal.. 400hp...
i will say that i want to run pre turbo WI with pump and see what i can do before giving e85 a chance.. but i think pump and WI will be my bread a butter on the s200SXE version of the 7670.
if you cant use E85, OR pump with WI.. then you can't hit 400 on the 7670.. and should go with the 8374.
with just pump only the 8374 is the better choice for 400hp.
Last edited by lastphaseofthis; Sep 11, 2016 at 09:40 AM.
You'll also be running substantially higher EMAP, EGT, IAT, and a lot more fuel(esp since we're using e85 in this hypothesis).
It was asserted in the 7670 thread that running 20+ psi to redline is actually encroaching on the efficiency of the turbo as a whole.
The 7670 doesn't want to make 400. The 8374 does it all day.
Do you want to squeeze every last drop out of that tube of toothpaste, or do you want a new tube?
Last edited by Narfle; Sep 11, 2016 at 01:02 PM.
Just the delta in boost pressure is an indicator of how much harder the 7670 has to work to make this power.
You'll also be running substantially higher EMAP, EGT, IAT, and a lot more fuel(esp since we're using e85 in this hypothesis).
It was asserted in the 7670 thread that running 20+ psi to redline is actually encroaching on the efficiency of the turbo as a whole.
The 7670 doesn't want to make 400. The 8374 does it all day.
Do you want to squeeze every last drop out of that tube of toothpaste, or do you want a new tube?
You'll also be running substantially higher EMAP, EGT, IAT, and a lot more fuel(esp since we're using e85 in this hypothesis).
It was asserted in the 7670 thread that running 20+ psi to redline is actually encroaching on the efficiency of the turbo as a whole.
The 7670 doesn't want to make 400. The 8374 does it all day.
Do you want to squeeze every last drop out of that tube of toothpaste, or do you want a new tube?
There nothing wrong with E50, and you are right about the knock benefit being very close (I saw the original presentation from the guy MIT researcher who did the ethanol % vs knock improvement study). You realistically need an ECU with a flex fuel code to make it work. Very few people on this forum have that. There's also the added inconvenience (minor for some, very annoying to others) of having to carefully monitor how you fill up. Most people here are running a Power FC, which under most setups runs fully open loop and just isn't sophisticated enough.
When you say the ECU adjusts it, what that really means is somebody has to tune it on a bunch of different blends and then hope the ECU interpolates it in a safe and usable way. If you want to run E50, you need to tune the car 3 times IMO. Tune on E0/E10, tune on E85, tune on E50. Now what "tune the car 3 times" means depends on what your goals are. Do you just want it to run on E50? Like run and drive and not blow up? Or does it have to have certain targets in terms of how well it starts and idles, how much power it makes, how it responds right after you fill up when you move between blends?
It can be as simple as fully tuning it on E85 and making a quick "ok, it's not going to blow up and driveability is tolerable" judgment on E50 and E10. Or it can be much more involved.
Depends so much on what the test procedure is, what the passing criteria is, and what emissions equipment is on the car.
When you say the ECU adjusts it, what that really means is somebody has to tune it on a bunch of different blends and then hope the ECU interpolates it in a safe and usable way. If you want to run E50, you need to tune the car 3 times IMO. Tune on E0/E10, tune on E85, tune on E50. Now what "tune the car 3 times" means depends on what your goals are. Do you just want it to run on E50? Like run and drive and not blow up? Or does it have to have certain targets in terms of how well it starts and idles, how much power it makes, how it responds right after you fill up when you move between blends?
It can be as simple as fully tuning it on E85 and making a quick "ok, it's not going to blow up and driveability is tolerable" judgment on E50 and E10. Or it can be much more involved.
Depends so much on what the test procedure is, what the passing criteria is, and what emissions equipment is on the car.
I have literally tuned a car on pump gas with a flex fuel sensor installed, topped it off with E85 to various levels( E30, E60, E80) and the tune was almost identical the entire way according to the logs.
Also E85 as mentioned does not seem to be too picky on the AFR so its not a big deal if its running rich or what one would consider lean on pump fuel.
We E85 every car we do here, and blowing engines is almost unheard of. Just this weekend we had an E85 car roadcourse at 30+ psi( making 630rwhp on a dynojet- streetported 13B). The car has been running E85 for about 2 years now without a single fuel system/engine issue.
Its ideal to run the ID1300/1700cc injectors as they have stainless internals which is ideal for alcohol based fuels, but we have yet to see an injector problem when running the correct filters( ID or stock etc).
I have used every possible combination of AI injection since early 2000. Aquamist developed the " summer " module for staged AI injection because of us.
E85 is the best mod for a turbo rotary car hands down.
As far as the 7670 debate goes you guys know we made 400rwhp at 15.5 psi on our 7670 kit with a fresh small streetport we built( E85). We also did 310rwhp @ 6.5 psi on pump with one of our large streetports...
Thread Starter
Joined: May 2005
Posts: 1,012
Likes: 45
From: North Dallas, TX
Thanks for chiming in Shawn (or Elliot?). I knew there was something about the injectors that was different but I couldn't quite remember what it was. Can you answer what E85 does with regards to passing emissions? More accurately, I currently pass emissions on stock twins with a midpipe that has a cat in it. I strictly use that pipe for emissions testing. Yes I still have the stock air pump. Will running E85 help with emissions? And if I run the EFR7670 do you think I could still pass? Again, using the catted midpipe for the test. My assumption here is that E85 drastically reduces hydrocarbon emissions due to less gasoline being in the fuel.
Also, to the people saying the EFR7670 isn't right for the power goal, I don't think that's quite right. 400whp seems to be the sweet spot as long as you're running the right fuel or using AI. Not only that, but the peak power isn't even what concerns me. The larger power band down low is really what I want.
Also, to the people saying the EFR7670 isn't right for the power goal, I don't think that's quite right. 400whp seems to be the sweet spot as long as you're running the right fuel or using AI. Not only that, but the peak power isn't even what concerns me. The larger power band down low is really what I want.
Also, to the people saying the EFR7670 isn't right for the power goal, I don't think that's quite right. 400whp seems to be the sweet spot as long as you're running the right fuel or using AI. Not only that, but the peak power isn't even what concerns me. The larger power band down low is really what I want.
But, to be fair.
A flex-fuel/AI-dependent 7670 pushing 400rwhp is pretty rad
A pump gas powerFC 8374 making 400rwhp is not that big a deal.
Every feature or condition on your performance is a potential complication
Much respect to Turblown and company. I'm a big fan.
But, we'd be blind if we didn't appreciate they have some invested interest in adaptronic flex fuel setups and prodigious horsepower outputs on the EFR platform.
YMMV. Just sayin'.
Go ride in some EFR cars and see what powerband you like the best!
Lord knows there are some fast FDs in TX.
Thanks for chiming in Shawn (or Elliot?). I knew there was something about the injectors that was different but I couldn't quite remember what it was. Can you answer what E85 does with regards to passing emissions? More accurately, I currently pass emissions on stock twins with a midpipe that has a cat in it. I strictly use that pipe for emissions testing. Yes I still have the stock air pump. Will running E85 help with emissions? And if I run the EFR7670 do you think I could still pass? Again, using the catted midpipe for the test. My assumption here is that E85 drastically reduces hydrocarbon emissions due to less gasoline being in the fuel.
Also, to the people saying the EFR7670 isn't right for the power goal, I don't think that's quite right. 400whp seems to be the sweet spot as long as you're running the right fuel or using AI. Not only that, but the peak power isn't even what concerns me. The larger power band down low is really what I want.
Also, to the people saying the EFR7670 isn't right for the power goal, I don't think that's quite right. 400whp seems to be the sweet spot as long as you're running the right fuel or using AI. Not only that, but the peak power isn't even what concerns me. The larger power band down low is really what I want.
Here is the 6.5PSI dyno,
Power-wise, the 8374 is the better fit for your 400 hp goal. Very little debate here. But if you are keeping the stock air pump, and are planning to pass emissions, then your choice will be limited to the 7670 unit since there is no standard EFR kit available that retains the stock air pump in combination with the 8374 turbo.
Suggest you discuss your overall goals with Chris & co. @ RP since it sounds like you know them already. Those guys will get you squared away with the best fit for your situation.
Suggest you discuss your overall goals with Chris & co. @ RP since it sounds like you know them already. Those guys will get you squared away with the best fit for your situation.
I didn't realize we have not uploaded a lot of the dyno charts etc on our site..
Here is the 7670 EFR IWG ( welded kit) on E50 flex fuel, with a fresh small street port( we built the entire car in house).
This car is pretty fast, and will annihilate most 400rwhp standard single turbo rx7s.
Here is the 7670 EFR IWG ( welded kit) on E50 flex fuel, with a fresh small street port( we built the entire car in house).
This car is pretty fast, and will annihilate most 400rwhp standard single turbo rx7s.
I did run it out farther, but I didn't save the correct dyno printout. I cannot remember if I was doing other cars that day or not, but probably. The graph basically just continues the same curve as shown, torque is heading down and HP is pretty much flat.
You can see I took it to 7200rpms in this video and its still pulling just fine.
You can see I took it to 7200rpms in this video and its still pulling just fine.
Thread Starter
Joined: May 2005
Posts: 1,012
Likes: 45
From: North Dallas, TX
^On that setup...why is boost tapering off at the higher RPM? is it because the compressor is just too small and can't keep up? Or was it simply tuned that way to meet fuel availability?