Welcome to the North American Subaru Impreza Owners Club Friday July 11, 2014
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Here you can view your subscribed threads, work with private messages and edit your profile and preferences Home Registration is free! Visit the NASIOC Store NASIOC Rules Search Find other members Frequently Asked Questions Calendar Archive NASIOC Upgrade Garage Logout
Go Back   NASIOC > NASIOC Technical > Engine Management & Tuning

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.
* Registered users of the site do not see these ads.
Reply
 
Thread Tools Display Modes
Old 09-21-2007, 02:00 PM   #1251
red5001
Scooby Newbie
 
Member#: 33942
Join Date: Mar 2003
Location: Roochester, NY
Vehicle:
04.5 STI
wrb

Default

Quote:
Originally Posted by red5001 View Post
They do break in some. That may be a factor. I actual don't rember the specifics of the break it. But that would be a contributing factor. I can try to talk with my friend he is a test engineer for injectors/fuel rails and works alot with alternative fuels. See if I can get some updated info/details.
Sorry itís been a while since I posted some info.

I briefly talked with my friend who works in the Injector industry regarding E85 and fuel injectors specifically. He did say if injectors are not designed for E85 they would greatly shorten the life of the injectors. He did say if regular gas is used along with E85 the life of these components last much much longer. Also some injectors from companies that have E85 injectors are the same as the regular ones so there maybe no difference or there regular injectors are robust enough to handle E85. That is on a case by case thing.

As most of you know He didn't suggest at all running E85 in a car that is not tuned for it so a stock car that is not E85 ready would not be a good idea since you will be running lean and not to mention the components in the car. He didn't have much info on fuel pumps.

Also was mentioned that manufactures of E85 are have some troubles with the consistency of batches of E85. So basically he didn't recommend using all of the time. Using it here and there probably wouldn't hurt much.

Hope that helps some.
* Registered users of the site do not see these ads.
red5001 is offline   Reply With Quote
Old 09-21-2007, 02:43 PM   #1252
LastResort
Scooby Guru
 
Member#: 99289
Join Date: Oct 2005
Default

I would love to see a pump designed for e85, just for the security of mind.
LastResort is offline   Reply With Quote
Old 09-21-2007, 05:40 PM   #1253
HamFist
Scooby Specialist
 
Member#: 2112
Join Date: Aug 2000
Chapter/Region: MWSOC
Vehicle:
2000 Impreza 2.5RS
BRP

Default

I still have leftover injectors if someone wants to look at those. They have 5k miles worth of E85 on them.

It's nice to see companies and enthusiasts working well together. There are practical solutions to common problems. What isn't confined to here is all the activity in other shops, corporations, government, BBS', and people's garages. This kind of work is getting serious attention from every angle and shows no signs of slowing. We're all having our own success with it this early in the game. That keeps people going to at least see where the trail goes. It's blossoming into every aspect of fuel use from production to end-user technologies to fabrication. This market is still taking shape, but has good momentum and direction. Nobody really wrote the book on all this stuff, but there's plenty of resources that fit well to get the job done.
HamFist is offline   Reply With Quote
Old 09-21-2007, 08:06 PM   #1254
hotrod
Scooby Specialist
 
Member#: 14141
Join Date: Jan 2002
Location: 13.239@102.85 @ 5800 ft on 13T
Vehicle:
2002 Impreza WRX
e85forum.net

Default

shoeboxrich:

Your comments have triggered some thoughts on this subject, and would like to know if you have tested these or have any views (don't want to put you on the spot) so will just throw these out there for general discussion.

1. The discussion about ungrounded pumps in plastic tanks would obviously raise the question about installing a secondary ground lead to the pump casing for people doing conversion with isolated ground pumps in plastic tanks or non-conductive fuel pump mounting systems.

2. What you discribe implies the issue is most likely a form of electrolytic corrosion due to the presence of water.

a. is the presence of water in the fuel detectable with simple electrical conductivity measurements of the fuel between two points in the fuel system? If yes, what is the cross over point in your tests where fuel conductivity becomes high enough that fuel system / pump corrosion becomes an issue. Can the average user measure this, or do we need to fabricate a "sensor" that would allow us to take fuel resistivity measurements?

b. Have you run any tests with a sacrificial annode (zinc etc.) installed in the uninsulated system to direct the corrosion away from the pump.

Third, I also am careful to buy fuel from a select few stations that I feel are trustworthy regarding the quality of their fuel, do any of the high corrosion fuel pump users mention buying fuel from the cut rate stations where water in the fuel might be more likely.

Larry
hotrod is offline   Reply With Quote
Old 09-22-2007, 04:55 AM   #1255
StiLimited
Scooby Newbie
 
Member#: 121212
Join Date: Jul 2006
Chapter/Region: SWIC
Vehicle:
2007 Sti Limited
Urban Gray Metallic

Default

Quote:
Originally Posted by red5001 View Post
Also was mentioned that manufactures of E85 are have some troubles with the consistency of batches of E85.
Did he provide a source for this rumour?
StiLimited is offline   Reply With Quote
Old 09-22-2007, 11:06 AM   #1256
wage0052
Scooby Newbie
 
Member#: 127556
Join Date: Sep 2006
Chapter/Region: MWSOC
Location: Minnesota
Vehicle:
2006 WRX
RomRaided.

Default

I can tell you second hand that this is the case.

One of the tuning enthusiasts here in MN was running an E85 tune (you may remember wall of tv's monster torque '06 wrx). He has mentioned on several occasions the need to datalog and re-tune after each fill up.
wage0052 is offline   Reply With Quote
Old 09-24-2007, 09:11 AM   #1257
shoeboxrich
Scooby Newbie
 
Member#: 148509
Join Date: May 2007
Default

Larry,
Thanks for your comments. I'll relay your points on to our engineers. I do know that they have run some component tests comparing grounded vs ungrounded that may end up being one of the key areas of concern. Beyond that I'm not sure what conclusions we have come to. I'll keep everyone posted though.
Rich
shoeboxrich is offline   Reply With Quote
Old 09-24-2007, 12:30 PM   #1258
red5001
Scooby Newbie
 
Member#: 33942
Join Date: Mar 2003
Location: Roochester, NY
Vehicle:
04.5 STI
wrb

Default

Quote:
Originally Posted by StiLimited View Post
Did he provide a source for this rumour?
I don't have an exact source but he has been working with suppliers and I believe he is presenting a paper to SAE on the subject in a month. Once he presents the paper I may be able to get some more info and or a copy.

http://www.sae.org/technical/papers/2007-01-4072

Also SAE has aother tech papers on the subject.

Last edited by red5001; 09-24-2007 at 12:38 PM.
red5001 is offline   Reply With Quote
Old 09-24-2007, 04:24 PM   #1259
hotrod
Scooby Specialist
 
Member#: 14141
Join Date: Jan 2002
Location: 13.239@102.85 @ 5800 ft on 13T
Vehicle:
2002 Impreza WRX
e85forum.net

Default

Thanks for the heads up on the SAE paper!!

Larry
hotrod is offline   Reply With Quote
Old 09-25-2007, 12:19 AM   #1260
prometheum
Scooby Specialist
 
Member#: 92003
Join Date: Jul 2005
Chapter/Region: International
Location: Tatooine
Vehicle:
04 bicycle!

Default

Quote:
It basically takes about a +30% increase in fuel flow to get the same equivalent mixture with E85 that you had with gasoline.
can you just scale your injectors 30% down and tune from there?
prometheum is offline   Reply With Quote
Old 09-25-2007, 01:49 AM   #1261
hotrod
Scooby Specialist
 
Member#: 14141
Join Date: Jan 2002
Location: 13.239@102.85 @ 5800 ft on 13T
Vehicle:
2002 Impreza WRX
e85forum.net

Default

If you don't run out of injector!

If you are near stockpower levels that will work (sort of like jacking your fuelpressure) it is workable to a point but not the proper solution.


Stock injectors are sized to run at 80% duty cycle at max power. To hit the stock power (or slightly above) on E85 you need +30% fuel flow so that means just to hit stock power levels you will run the injectors to static by about 10%, that will make you lean at max injector flow. Add any upgrades like a bigger turbo and you could melt an engine.

I went from the stock 440's to 550 cc injectors on my 2 L with the stock TD04-13G and was running in the 90% duty cycles with the 16G I ran out of injector even on a conservative tune with the 550's.

Larry
hotrod is offline   Reply With Quote
Old 09-25-2007, 04:58 AM   #1262
prometheum
Scooby Specialist
 
Member#: 92003
Join Date: Jul 2005
Chapter/Region: International
Location: Tatooine
Vehicle:
04 bicycle!

Default

Quote:
Originally Posted by hotrod View Post
If you don't run out of injector!

If you are near stockpower levels that will work (sort of like jacking your fuelpressure) it is workable to a point but not the proper solution.


Stock injectors are sized to run at 80% duty cycle at max power. To hit the stock power (or slightly above) on E85 you need +30% fuel flow so that means just to hit stock power levels you will run the injectors to static by about 10%, that will make you lean at max injector flow. Add any upgrades like a bigger turbo and you could melt an engine.

I went from the stock 440's to 550 cc injectors on my 2 L with the stock TD04-13G and was running in the 90% duty cycles with the 16G I ran out of injector even on a conservative tune with the 550's.

Larry
right, but i've got modified stockers in there now flow tested at 820cc; is it safe /wise to scale back the injectors 30% (i.e. tell the utec they are say 570cc) and tune from there?
prometheum is offline   Reply With Quote
Old 09-25-2007, 05:39 AM   #1263
hotrod
Scooby Specialist
 
Member#: 14141
Join Date: Jan 2002
Location: 13.239@102.85 @ 5800 ft on 13T
Vehicle:
2002 Impreza WRX
e85forum.net

Default

That is basically what I have on mine. I also have the decapitated injectors and scaled them down to 550 if I remember correctly (need to check my notes). On 17 psi on E85 I was getting 281 awhp (330+ at the crank) from a 2.0L and 16G small, and I still had available injector capacity.

Larry
hotrod is offline   Reply With Quote
Old 09-25-2007, 01:11 PM   #1264
scoobdude
Scooby Specialist
 
Member#: 50699
Join Date: Dec 2003
Chapter/Region: TXIC
Location: austin
Vehicle:
2004 WRX
Platinum Silver

Default

Hotrod, I calculated required injector a little different. Pleae read below to see if this makes sense?

Provided the following is true: 440 = stock injector, E85 need 30% more fuel and stock injectors hit 80% IDC on pump gas at stock power levels

Then:
440cc X 80% = 352cc
Now lets add another 30% more fuel: 352 x 130% = 457.6cc

So while you would still run static, you are only overshooting your injectors by 4% (457.6 - 440 = 17.6/440 = 4%)

Does that make sense?

Also when calculating this also remember that will be fluctuations in temperature and altitude that your car will compensate for. However your injectors will not get any bigger.

And btw, I am able to max out the stock injectors with only 7lbs on th stock turbo with E85. And thi is with fueling scald back from that stock 10:1 target.
scoobdude is offline   Reply With Quote
Old 09-25-2007, 05:24 PM   #1265
hotrod
Scooby Specialist
 
Member#: 14141
Join Date: Jan 2002
Location: 13.239@102.85 @ 5800 ft on 13T
Vehicle:
2002 Impreza WRX
e85forum.net

Default

At 457.6 cc per min that means you are running the injectors static, ie wide open which is not good. They size them at 80% for a reason so the actuator coils do not over heat etc. It also means at max fuel flow you will be going lean by over 4% because it is physically impossible for those injectors to flow 457.6 cc/min at stock fuel pressure, if you get them flow tested you will see they might only flow 420 cc/min ---- 440 is only the nominal flow rate. The 80% sizing allows for the variation between injectors as well.

To maintain your 80% duty cycle under E85 you need injectors 1.30x the size as your stock injectors, or 440x1.30 = 572 cc/min.

Anything less than that and you are running your injectors too hard (by industry standards) Everyone gets away with it for a while but I do know folks have melted pistons because undersized injectors hung up at WOT and did not flow properly. If you run an injector at too high of an injector duty cycle they can go into a weird never off never on condition expecially if you have low system voltage for some reason. The ECU simply cannot actuate them fast enough to get the design flow out of them, and this can result in serious lean outs. A 550 cc/min is the smallest I would recommend on E85 at near stock power levels. Your 820 cc/min injectors get iffy at somewhere in the 450 hp (at the crank) power level and up, and will be static at about 550 hp at the crank for a ball park number.

Larry
hotrod is offline   Reply With Quote
Old 09-25-2007, 07:01 PM   #1266
StiLimited
Scooby Newbie
 
Member#: 121212
Join Date: Jul 2006
Chapter/Region: SWIC
Vehicle:
2007 Sti Limited
Urban Gray Metallic

Default

I have a good understanding of the WOT issues with E85. But what I can't quite get my head around is the closed loop operation. If you use a stock O2won't the computer keep trying for the wrong a/f ratio?

Doesn't it require something like an programmable WB O2 to "fool" the computer so that it targets the correct a/f?
StiLimited is offline   Reply With Quote
Old 09-25-2007, 08:07 PM   #1267
scoobdude
Scooby Specialist
 
Member#: 50699
Join Date: Dec 2003
Chapter/Region: TXIC
Location: austin
Vehicle:
2004 WRX
Platinum Silver

Default

No because it looks for lambda not a/f. 1 lambda = stoich. Or 14.68:1 a/f on gas, 9:1 a/f on Ethanol and 6:1 on methanol (not sure if i have those number right).

So basically your O2 sensor is doings its job, and if you read your data as a/f without changing the fuel type setting you will still see 14.7:1

Hope that makes sense cause i just confused myself
scoobdude is offline   Reply With Quote
Old 09-25-2007, 08:18 PM   #1268
Brady12
Scooby Specialist
 
Member#: 80923
Join Date: Feb 2005
Chapter/Region: MAIC
Location: Nova
Vehicle:
2008 FXT (XT Sport)
WRB

Default

Not to Hi-Jack, but I have about 40Gal of E85, that I was running on my STi avaible for sale.

I'm in the DC Metro area, and I will offer it at $1.25 per gallon.

Pump available, or take the whole drum
Brady12 is offline   Reply With Quote
Old 09-25-2007, 09:20 PM   #1269
StiLimited
Scooby Newbie
 
Member#: 121212
Join Date: Jul 2006
Chapter/Region: SWIC
Vehicle:
2007 Sti Limited
Urban Gray Metallic

Default

Quote:
Originally Posted by scoobdude View Post
if you read your data as a/f without changing the fuel type setting
When you say "change the fuel type setting" where and what are you changing?
StiLimited is offline   Reply With Quote
Old 09-25-2007, 09:29 PM   #1270
hotrod
Scooby Specialist
 
Member#: 14141
Join Date: Jan 2002
Location: 13.239@102.85 @ 5800 ft on 13T
Vehicle:
2002 Impreza WRX
e85forum.net

Default

He means most widebands compute the AFR from the lambda assuming you are running gasoline, so stoich shows as an AFR of 14.6-14.7 more or less. A few wide bands allow you to tell the meter what fuel you are running (like methanol or gasoline). None that I know of have a fuel type setting for E85.

Easier just to think in lambda or gasoline AFR and not worry about it. All you really care about is if the engine is running well and it is not too lean. On a gasoline calibrated wide band on 100% E85, I see AFR's of 14.7 - 15.0 during closed loop light throttle cruise, and 11.2 (lamda 0.76) -11.5 (lambda 0.78) or so at WOT.

Lambda's at WOT are somewhere in the mid 0.7x or if you want to go for fuel economy at moderate boost you can get away with lamda's of 0.82 or so at WOT.

Larry
hotrod is offline   Reply With Quote
Old 09-25-2007, 09:44 PM   #1271
StiLimited
Scooby Newbie
 
Member#: 121212
Join Date: Jul 2006
Chapter/Region: SWIC
Vehicle:
2007 Sti Limited
Urban Gray Metallic

Default

So this assumes you are running a wide band and using the take off from it to feed the ecu, correct?

And running of a ratio of e85 to gas like 50/50 or something like that would mean ... something custom. I think the innovate allows you to do this, but I'm not positive.

But running a factory O2 sensor.... that's what I'm wondering about... If you were to just fill up with E85, and it's trying to get 14.7... (Cause it assumes you have gas in the tank) that is going to be too lean during closed loop correct?
StiLimited is offline   Reply With Quote
Old 09-25-2007, 11:28 PM   #1272
RP31
Scooby Specialist
 
Member#: 123574
Join Date: Aug 2006
Chapter/Region: MWSOC
Location: Lisle, IL
Vehicle:
2005 2.6L 9:1 425WHP
CGM STi

Default

Quote:
Originally Posted by hotrod View Post
He means most widebands compute the AFR from the lambda assuming you are running gasoline, so stoich shows as an AFR of 14.6-14.7 more or less. A few wide bands allow you to tell the meter what fuel you are running (like methanol or gasoline). None that I know of have a fuel type setting for E85.

Easier just to think in lambda or gasoline AFR and not worry about it.
The TXS Tuner has this feature (it doesn't specifically say "E85", but you can adjust settings to set it up appropriately.

I didn't bother though, because you're right... It is easier to just think in gasoline AFR.
RP31 is offline   Reply With Quote
Old 09-26-2007, 01:41 AM   #1273
hotrod
Scooby Specialist
 
Member#: 14141
Join Date: Jan 2002
Location: 13.239@102.85 @ 5800 ft on 13T
Vehicle:
2002 Impreza WRX
e85forum.net

Default

Quote:
But running a factory O2 sensor.... that's what I'm wondering about... If you were to just fill up with E85, and it's trying to get 14.7... (Cause it assumes you have gas in the tank) that is going to be too lean during closed loop correct?
No I am talking about the stock O2 sensor driven OEM ecu. Or a reflashed ECU. The O2 sensor used in closed loop as already mentioned above only reads lambda and tries for a lambda 1 on any fuel in closed loop. It could care less if you are running gasoline, toluene, kerosene or E85 all it looks for is unburned oxygen in the exhaust gasses. It will look for and attempt to get to a lambda 1 (14.7 on gas). As long as it has enough fuel trim to reach lambda 1.0 it is fat dumb and happy.

The stock ECU can successfully adjust to up to about 30% blend of E85 and gasoline. At 30% - 50% blends it will throw a CEL and be a bit lean in closed loop but will still work "ok" but you will be quite lean in open loop.
If you install larger injectors +30% fuel flow, the stock ECU is quite happy on 100% E85 in closed loop. It only has problems going rich enough in open loop.

I happen to log with a wideband but its O2 sensor also only sees the lambda, the internal electronics converts that to an AFR number but it assumes you are running gasoline so stoich mixture or lambda 1 appears on the display as 14.7 AFR.

Your making this too complicated, the O2 sensor works just fine in closed loop on E85 the ecu only complains if it does not have enough adjustment to get to its target of lambda 1. If you add some fuel flow (anything over 15% additional fuel) the stock ECU will be able to tune to lambda 1 in closed loop, without throwing a CEL.

You only really need custom tuning in open loop once you have enough fuel added to run closed loop without a CEL.



Larry
hotrod is offline   Reply With Quote
Old 09-26-2007, 02:09 AM   #1274
StiLimited
Scooby Newbie
 
Member#: 121212
Join Date: Jul 2006
Chapter/Region: SWIC
Vehicle:
2007 Sti Limited
Urban Gray Metallic

Default

Quote:
Originally Posted by hotrod View Post
Your making this too complicated,

Story of my life.

Thanks again for the explanation. I'm starting to understand it now.
StiLimited is offline   Reply With Quote
Old 09-26-2007, 10:32 AM   #1275
scoobdude
Scooby Specialist
 
Member#: 50699
Join Date: Dec 2003
Chapter/Region: TXIC
Location: austin
Vehicle:
2004 WRX
Platinum Silver

Default

another thing that might help, is the fact that alot of gas has 10% Ethanol now. If the O2 sensor was only able to look for a/f ratios, then we would actually be running our car to rich as the target a/f ratio for E10 = 14.1:1 i believe.

But here are 2 great wiki articles i found which will also probably help

Air-fuel ration: http://en.wikipedia.org/wiki/Air-fuel_ratio
Oxygen Sensor: http://en.wikipedia.org/wiki/Oxygen_sensor

Hope that helps.

Hotrod, might wanna add those to the first pages of this thread.
scoobdude is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
What do you need to do to use E85 fuel? wantsti Rocky Mountains Impreza Club Forum -- RMIC 37 02-20-2014 01:27 AM
E85 fueling question- 850cc + fpgreen...adjustable FPR? Blown95ImpalaSS Factory 2.5L Turbo Powertrain 5 09-29-2009 07:37 PM
E85-Fueled Z06, 30th Anniversary Corvettes to Pace Ď08 Indy 500 AVANTI R5 Non-Subaru News & Rumors 0 12-27-2007 01:56 PM
E85 fuel available now in Arvada 9/22/06 hotrod Rocky Mountains Impreza Club Forum -- RMIC 9 09-25-2006 02:29 PM
E85 Fuel in Austin? When? dromango Texas Impreza Club Forum -- TXIC 8 06-29-2006 01:32 PM


All times are GMT -4. The time now is 11:16 AM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2014 Axivo Inc.
Copyright ©1999 - 2014, North American Subaru Impreza Owners Club, Inc.