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01 VDC, 05 R Sedan, 06 BAJA EJ257
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Discussion Starter #1
I removed defective CATs and installed straight pipes. This car is tuned to run E85. It runs too rich on gasoline, so E85 is the primary fuel. The video is pretty much self explainatory.

CATs will go back in, I just did this as an experiment and to gather data.
The bad CATs had to come out anyway. The car was running crappy.

Video: https://www.youtube.com/watch?v=kymiztuB5gI


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03 H6 OBW & 06 WRX Sportwagon
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18,107 Posts
can you run the same injectors and pump for both?
 

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01 VDC, 05 R Sedan, 06 BAJA EJ257
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Discussion Starter #5
More air needs more fuel. I have 410 cc injectors to supply the fuel. I am going to upsize to 650 cc to get even more. When the ECM was remapped for the supercharger, the injector latency was changed in order to get the proper fuel shot for the added air charge, along with the timing and knock retard. The last three logs I ran was on E85 and the latency was changed after each to gain the perfect mix, what I have now.

I also have a larger volume fuel pump. The OE fuel pump will supply the necessary flow needed for E85 everyday driving. I just wanted to be sure it would be capable to provide flow for "racing" where the engines runs from 4-7k rpm.

An NA or forced induction engine can be remapped to perform better and gain in fuel economy. To run E85, the latency is increased to provide a longer period of open since the combustion process needs a higher volume of alcohol to get the same burn as gasoline. Generally, 25% more volume is needed. Given the injectors can operate safely up to 85%, I would think that a NA engine can be reprogrammed to run E85 safely, unless you keep the engine rpm on the high side, then you would need to up the injector size. But, when the fuel map is changed to run E85, when gasoline is put in it will run rich. The car doesn't distinguish between the two fuels. It doesn't have an alcohol monitor or capability to switch its map. That would be up to the operator. Switching programming takes less than 3 minutes. If you do the remap, save the original ROM or an updated one on the laptop. Run the E85 program for E85. Switch to the OE or modified for gasoline.

I can run gasoline in the car with the map I run for E85 and keep the mix at stoichiometric for gas. It just doesn't run as well for power output and I have to watch the AF gauges to make sure I don't go rich by changing my foot position on the accelerator. It's just a matter of throttle control.

For math calculation, 14.7:1 is for gas, 9:1 is prime for alcohol.
 

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01 VDC, 05 R Sedan, 06 BAJA EJ257
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Discussion Starter #6
And the second video is running gasoline on the map used to run E85.
 

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2001, European Outback, H6
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150 Posts
...

I also have a larger volume fuel pump. The OE fuel pump will supply the necessary flow needed for E85 everyday driving. I just wanted to be sure it would be capable to provide flow for "racing" where the engines runs from 4-7k rpm.

An NA or forced induction engine can be remapped to perform better and gain in fuel economy. To run E85, the latency is increased to provide a longer period of open since the combustion process needs a higher volume of alcohol to get the same burn as gasoline. Generally, 25% more volume is needed. Given the injectors can operate safely up to 85%, I would think that a NA engine can be reprogrammed to run E85 safely, unless you keep the engine rpm on the high side, then you would need to up the injector size. But, when the fuel map is changed to run E85, when gasoline is put in it will run rich. The car doesn't distinguish between the two fuels. It doesn't have an alcohol monitor or capability to switch its map. That would be up to the operator. Switching programming takes less than 3 minutes. If you do the remap, save the original ROM or an updated one on the laptop. Run the E85 program for E85. Switch to the OE or modified for gasoline.

...

For math calculation, 14.7:1 is for gas, 9:1 is prime for alcohol.
Sorry, but what do you mean by "NA engine"?

E85 is about 40% cheaper where I live. But I don't plan to do any big changes to the engine if I can avoid it. Besides switching the map, what changes would you do to a stock H6 to run E85? You said that you think that the injectors can stay but what about the fuel lines and the injection system. Wouldn't the alcohol harm the rubber when it is in there four too long? Did you make any bad experiences with that?
 

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2004 Outback Wagon, 2.5, 4EAT, All weather package.
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1,036 Posts
Sorry, but what do you mean by "NA engine"?
NA means Normally or Naturally Aspirated (depending on who is talking). Meaning there is no form of forced induction (via a supercharger or turbo charger). Cardoc's car is supercharged, so it has forced induction rather than being NA.
 

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01 VDC, 05 R Sedan, 06 BAJA EJ257
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Discussion Starter #9
So far, at 8k miles running E85, I have only had one issue with fuel and I don't think it was due to the alcohol. A fuel hose split at my Aeromotive pressure regulator. I think I got a bad roll of hose.

All the seals were new when I installed the upsized injectors. I had them out a couple thousand miles ago and so far, no swelling. The hoses at the tank are doing great as well as the other OE hoses I left in place. Its all in the name of science, so don't say it. Besides, I have extra fuel hose in the car with tools. I would expect a failure in the hoses first since they get the most flow and volume with fuel going to the engine and then back to the tank.

Crossgolf, a good remote tuner can remap your ECM. Ed at XTreme Racing Tuning did mine and knows what needs to be done to make it work without a MAF sensor and without using the MAP sensor wholly. Tell him CarDoc sent you. He's good people and only maps Subaru. He drives one.
 

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1993 Legacy LSi with still functioning Air Suspension, 1999 Outback 2.5L 5MT lab Rat
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191 Posts
Not sure what Mapping your using, but 3 things come to mind, 1st HC #'s as high as your video showed on E85 would be labeled a Gross polluter in any CA Emissions State, there are only 7 states Currnently Running a CA. style program so there is that. 2nd if your running E85 your numbers should be much lower than GAS since Ethanol is NOT a Hydrocarbon Fuel and only 15% of E85 is Gas. 3rd if your already know your running rich, increasing the Injector Flow size isn't nessesarily the answer. I smog 6 Cyl Subarus regularly, and seldom see HC readings above 5-10ppm, and CO numbers above .02% since Ca. exempts cars for the 1st 6 years of ownership most of these cars are well past 60K when they get their 1st Emissons Check. The upside is Gas is More efficent, and thus less expensive in the long haul. I would look more closely at why its running rich, rich isn't nessesarily bad for the engine especially if it is Supercharged, the problem is the The Catalytic Convertors which do not like rich mixtures over long periods of time. You mentioned Injector Latency, I wonder have you given any consideration to Air/Fuel ratio sensor Latency, as well? I have had GM cars drop P0420 codes for lazy AF Ratio sensors. I assume that your running a hybrid of electronic Injector control and an adjustable fuel pressure regulator or have you found a way to control the fuel pressure with load changes/demands? Just my thoughts....
 

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01 VDC, 05 R Sedan, 06 BAJA EJ257
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Discussion Starter #12
I am running the factory installed Denso ECM to manage the car. No piggyback. The video is without CATs. I run E85 for more punch and therefore needs to run richer. It does not run rich all the time on gas, only when I punch it. Since the injectors are pulsing to provide necessary volume to combustion running the alcohol, and alcohol is my primary fuel, when gasoline is put in and the computer can't distinguish between alcohol and gas, if I get on it with gas, I lose power and torque output because it will run as high as 9:1 and the timing won't correct for this. Again, because it was programmed running E85. Even with gas it puts out more power/torque over stock, but lacks due to an overly rich mix.

With the E85, again stoichiometric for alcohol is 9:1, a rich measure for gas is perfect for alcohol. The combustion process burns most of the fuel and also assist in burning majority of the oxygen. Look at the video again. The O2 levels are down as if CATs were installed and CO2 values is good also. It's an efficient burn. The HCs are due to the gas and additives in the fuel in combination with nitrogen and whatever other contaminates are in the air being pulled/pushed in to the engine.

The reason for going to larger injectors again is to provide more fuel to the combustion process at high rpm. The current injectors will run 87% duty and the car starts to lean out more than I like. I don't want pre-ignition or detonation at 6500+ rpm at high speed. That could be damaging and dangerous. I may have been the first to do this kind of build, but I won't be the first to melt the engine. A lot of builders screw the pooch because they don't understand the physics involved and listen to poor advice or just can't get the combustion mix proper for what they are trying to get out of the engine. I'm not that builder.

With the CATs installed, 0, ZERO HCs out the tailpipe. It's like hot air out a dryer vent. Along with a shite load of power. :29:

My build is here if you haven't seen it yet: http://www.subaruoutback.org/forums/110-gen-2-2000-2004/47896-sleeper-vdc.html

Also, read Fibber2's thread here: http://www.subaruoutback.org/forums...spective-p0420-catalytic-efficiency-code.html
 

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01 VDC, 05 R Sedan, 06 BAJA EJ257
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Discussion Starter #13
On AF sensors: All 4, yes four, match in data with exception to the OE sensors which only show up to 11.5:1. The ECM can't see a richer mix than 11.5. But my wideband VW Bosch sensors in combination with the gauges do show richer mixtures. Also, the EGT let's me know what's going on in combustion while cruising and at 100% load.
 

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1993 Legacy LSi with still functioning Air Suspension, 1999 Outback 2.5L 5MT lab Rat
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Sounds like fun as long as the driveline holds up, As far as E85 performance vs Gasoline is concerned for the application you are running. I'm not sure about Texas but here E85 is as much as 89 Octane Gas and since Alcohol is Not as efficent in terms of MPG as Gasoline, except in applications where people are running w/o the Catalysts for Racing/Autocrossing etc. and High Boost Applications High E85 use is limited to specific geographic regions where the Political climate is Global Warming Sensitive.
 

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05 OBXT 5eat stg1.2
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Have you tried leaning out your AFR and increasing timing? That is the benefit of running e85. Are you tuning to the point of knock then backing off?
 

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DIY-Turbo 2.2l OBS 12.89s 1/4mile @ 106.17MPH
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Sounds like fun as long as the driveline holds up, As far as E85 performance vs Gasoline is concerned for the application you are running. I'm not sure about Texas but here E85 is as much as 89 Octane Gas and since Alcohol is Not as efficent in terms of MPG as Gasoline, except in applications where people are running w/o the Catalysts for Racing/Autocrossing etc. and High Boost Applications High E85 use is limited to specific geographic regions where the Political climate is Global Warming Sensitive.
E85's lower cost per gallon means that your cost per mile may equal or even better your cost per mile vs gasoline - Flex fuel folks found in order to break even vs gasoline E85 has to be $.50 cheaper per gallon.

If you are a high boost / high performance guy running race gas E85 is a fraction of 117 Octane C16 costs.

C16 is about $100 for a 5 gallon can around NYC while EXPENSIVE E85 @ $4.00 / gallon ($3.50/gal is more realistic) will cost just $20 for 5 gallons or $26 if you take into account the fact you'll burn a bit more e85 vs. gas - either way the cost is SIGNIFICANTLY Lower...
+
Folks I know that have switched from C16 to E85 have actually made more power with pump E85 than they made with expensive C16 - both fuels require a roadtrip to aquire here in NYC.
 

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Discussion Starter #17
The AFR data from the sensors shows 14.3:1 average cruising and 9.2 on the floor while accelerating. The change begins at about 5800 rpm where the fuel injectors begin reaching the limit but the car wants to keep going. It does keep going even as it begins to lean out, keeping the power curve on the uprise.

If I had a more consistent fuel mix up to 7k, It will perform better.

Timing and knock control were part of the remapping.

As for cost, the E85 comes out cheaper. I now get 12-14 mpg with E85 or gasoline. E85 is .25 cheaper than low grade, .75 cheaper than the 93 I pumped in daily.

The driveline holds up good. As does the suspension. Poly in the rear diff and trans mounts. All the suspension bushing remain tight. The only transmission issues I have is with the builder getting it right since the first rebuild long before the SC. It now needs a valve body. I think they screwed it up when the shift kit was installed. I have the JDM in the car, so I will swap the valve body from it to the kitted trans.

So if anyone needs a 02 VTD 4EAT from japan minus a valve body, let me know. It shifts great.
 
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