Tuning for E85

[wordy1]

Been doing some reading and with the A/F ratio being much lower than gasoline, will I be needing to completely change all of the values on the PE/AE tables to fully utilize the benefits of E85? Not to mention change the overall A/F ratio for all conditions? I want to start with a 50/50 mix and then move up to a 25/75 mix, which is what I've read to fully optimize the benefits of E-85. I'll be running the car in all climates and when I add ALKY, there will be no reason to go any higher.

Have you guys been able to get by, by just adding fuel and timing as needed for your mixture, with the tables already loaded onto a chip like Eric's?

About all I have the ability to tinker with currently are the user adj. features on my TT chip.

Will something a little more sophisticated than Powerlogger and a wideband O2 be needed for logging data?

I was going to post the data I logged and the changes I've made, but my comp. froze, and don't want to do all that again.

Been running a 25% mix of E85 and premium with nothing but positives to report. Car was running a bit rich before and I've only had to up the fuel slightly.

So far here's what I've noticed: smoother idle, better off idle response, NO KNOCK up to 20 psi on 20 Degrees of timing, a lower tone to the exhaust at cruise, noticeably quicker spool-up. In general the car "feels" like it just got a tune-up. And I'd imagine that the Ethanol helped to clean out the fuel system as well.


Milage is down only slightly, I'd guess say 30 mpg down to 27-28. Not sure if I can expect worse with a higher percentage, but then again, I am sure the car is not perfectly tuned, as its still a work in progress, but the results I've observed so far speak for themselves. Never have I been able to run 20 psi out of this car with this chip with anything but either race gas or at least 20% toluene. O2's look good, and the injectors still have some room left to go. And never has the car "felt" so good for normal driving.

Before I up the percentage, what fuel filter do I need to change to?

 

[Hot Air]

I see that you are running Red's XP+ pump. I'm not familar with it but will guess it is E85 compatible. Are you still running the stock fuel sock (pre-pump filter) and fuel filter (post-pump filter)? If so, you will eventually have trouble as (according to Aeromotive) the alcohol will attack (swell) the cloth/paper filters. Stainless steel is the best for E85. Let me know what you are running on the fuel system.
Conrad

 

[wordy1]

Basically its an upgraded Walbro 340, I'm told there are only slight improvements, if any.. I just replaced what was in the car before. Yes, the sock is a paper element. Haven't had to replace the post pump filter, so I cannot say for sure what it is, guess its time to find out.. But I'd imagine its just the stock filter. What sock do I need to change to?

I've spoken to Red about his pump, its compatible with E-85, but he cannot guarantee it, I will accept that risk as I won't be running pure E85 anytime soon... 25% E85 and 75% gas is as far as I will ever go on the 65# injectors I am planning on. And honestly can't see myself needing to go any higher than a 50/50 mix with ALKY.

Red's pump is good into the low 10's on gas, not sure if I'll need to upgrade, it'll be trial and error...

I've asked this NUMEROUS TIMES on MANY forums, and still have no idea how to measure the actual fuel voume, no one seems to know.. To me thats more important than the pressure and I would like to know how much actual volume I am getting. Got any ideas Conrad?

Thanks man, Scott.

 

[wordy1]

Conrad, have you noticed all the same benefits I am observing? The car just totally "feels" different, like the accelerator is looser or something.. MUCH better throttle response. A little tap and your stuck in the seat, I love this stuff.

I am wondering why the toluene didn't do this and why the E-85 does, it cannot have anything to do with octane, as Toluene is over 117 octane.
I was just able to eliminate the KR with it, I noticed no other differeneces. Even with the small percentage of E85, the car is totally transformed.

 

[Hot Air]

Scott,
I don't know of any simple way to actually measure the fuel flow. I do know how to calculate it for any given horsepower (fuel flow) and boost (fuel pressure) output. How much HP and boost do you want your fuel system to support? What duty cycle are you comfortable running on your injectors?
Conrad

 

[RmvBfrFlght]

To measure the fuel pump delivery capacity:

Disconnect the return line from the FPR
Connect a line from the return port of the FPR and place it into a container
Run pump for say 1 minute exactly (use a stop watch if required)

The volume or weight of fuel in the container will be the fuel pump volume for 1 minute. Can do some math to figure it for #/hr, gallons/hr or whatever measurement is desired.

By measuring the flow from the FPR return port it is taking into consideration the pressure against the pump. This is important. A fuel pressure gauge would also be helpful to measure the fuel pump (FP) head pressure. Along with a voltmeter to measure the FP voltage. A change in the FP voltage will change the capacity of the FP.

Between the head pressure, voltage, and volume from the return port the FP capacity is known.

Can also change the fuel pressure to a higher setting, such as it would be under boost, and do the same volume/weight measurement.

Can also change the FP voltage and do the same volume/weight measurement.

Obviously this is done with the engine off. And with great care as a spark will ignite the fumes.

RemoveBeforeFlight

 

[wordy1]

Scott,
I don't know of any simple way to actually measure the fuel flow. I do know how to calculate it for any given horsepower (fuel flow) and boost (fuel pressure) output. How much HP and boost do you want your fuel system to support? What duty cycle are you comfortable running on your injectors?
Conrad

Well I don't want to be running up to 100%. Thats all I know for sure.

Looking for a totally streetable car (smooth idle, great throttle response, quick spool-up, and reliability), with the ability to go to the track and get great gas milage on the way there and the way home..

This car will be a weekend driver/highway cruiser/crusie-in attender/car show attender/drag racer.. And if I really need to get some groceries with it, I can. About all I wish I had was A/C and cruise control, but it would cost more than what its worth.

Don't want to have to deal with excessive tuning and all that, just want to fill it up with gas/E85 and ALKY and go to the track.. And in a perfect world I'd like to have the ability to run just gas when I cannot find an E85 station. And I may be able to do so by just adding more ALKY.

My goal is to get this car a consistent 12 flat car on street tires without the need to buy race gas and turn things up when I get to the track. With the potential for consistent low 11's with drag radials. Its actually pretty close to that now with race gas, its just really expensive, hard to find near me, and a LOT of effort has to go into tuning once I get to the track when I am finally able to get it. Most of my runs thus far have been on premium with up to 20% toluene.

As Ron Popeil says, I'd like to "SET IT AND FORGET IT" :tongue:

 

[wordy1]

To measure the fuel pump delivery capacity:

Disconnect the return line from the FPR
Connect a line from the return port of the FPR and place it into a container
Run pump for say 1 minute exactly (use a stop watch if required)

The volume or weight of fuel in the container will be the fuel pump volume for 1 minute. Can do some math to figure it for #/hr, gallons/hr or whatever measurement is desired.

By measuring the flow from the FPR return port it is taking into consideration the pressure against the pump. This is important. A fuel pressure gauge would also be helpful to measure the fuel pump (FP) head pressure. Along with a voltmeter to measure the FP voltage. A change in the FP voltage will change the capacity of the FP.

Between the head pressure, voltage, and volume from the return port the FP capacity is known.

Can also change the fuel pressure to a higher setting, such as it would be under boost, and do the same volume/weight measurement.

Can also change the FP voltage and do the same volume/weight measurement.

Obviously this is done with the engine off. And with great care as a spark will ignite the fumes.

RemoveBeforeFlight

I was thinking of doing the same thing, but was hoping there is a guage somewhere that can read volume, to me actual volume is more important than the pressure and knowing how much fuel your pump is actually capable of delivering is what we all need to know. Will my pump be able to deliver the same amount of E85 as gas? The viscosities and lubricity are different..

What should I raise my fuel pressure at idle when running a 25% blend of E85 and 75% gas?

 

[wordy1]

My biggest concern is actually in regards to the AE/PE enrichment tables which are set for gasoline and its stoich. A/F ratio.. the E85 is much lower and will need more fuel.

Can I just add fuel and get away with that, or will I actually need to completely change all the settings across the board to optimize it for the blend I am planning?

 

[Hot Air]

Wordy,
Check out the other posts on this E85 Forum. I think you will find the answer there.
Conrad

 

[stickman]

Conrad, have you noticed all the same benefits I am observing? The car just totally "feels" different, like the accelerator is looser or something.. MUCH better throttle response. A little tap and your stuck in the seat, I love this stuff.

I am wondering why the toluene didn't do this and why the E-85 does, it cannot have anything to do with octane, as Toluene is over 117 octane.
I was just able to eliminate the KR with it, I noticed no other differeneces. Even with the small percentage of E85, the car is totally transformed.

The difference you are feeling is probably because the ethanol has a cooling effect on the intake charge, just like alky injection kits. Some people have reported EGTs dropping by 100F on 100% e85.

 

[86SS86LS]

Milage is down only slightly, I'd guess say 30 mpg down to 27-28. Not sure if I can expect worse with a higher percentage, but then again, I am sure the car is not perfectly tuned, as its still a work in progress, but the results I've observed so far speak for themselves. Never have I been able to run 20 psi out of this car with this chip with anything but either race gas or at least 20% toluene. O2's look good, and the injectors still have some room left to go. And never has the car "felt" so good for normal driving.

A little off topic, but how do you manage to pull down 30 mpg? I get around 20 mpg and the highest I've heard of is 25 mpg.

 

[BlackoutDrunk]

Hey Wordy I'm with you. I want to use E85 the same way. I don't really think A full conversion is what I want. I want to be able to mix it with regular gas for the benefits and results. If you find another post/article then please post here.

 

[Hot Air]

FWIW, I understand that the new FAST XFI can interface with an available GM fuel sensor. This enables XFI to automatically make changes to the tune depending on the fuel in the tank!
Conrad

 

[wordy1]

A little off topic, but how do you manage to pull down 30 mpg? I get around 20 mpg and the highest I've heard of is 25 mpg.

3.42 gear, plus taller tire (28"), plus lock-up convertor, plus great tuning=29-30mpg. This is a non-A/C car, optionless, lightweight factory car. Not sure if that helps much, but I've never done worse than 28 mpg since I've owned it. Irregardless, there was a noticeable drop in milage. It just depends on how you drive these cars. At 72 mph it gets 30, why 72? I don't know, it gets worse at lower and higher mph's. Gets about 20 in the city too when I drive like a grandma.

 

[wordy1]

Hey Wordy I'm with you. I want to use E85 the same way. I don't really think A full conversion is what I want. I want to be able to mix it with regular gas for the benefits and results. If you find another post/article then please post here.

Yep 25% E85 and 75% gasoline sounds like the magic mixture, which makes me wonder why they didn't make E65 or something in that range.

 

[bsdlinux]

Yes thats a good mixture, but I've made more power on a 50/50 mix no other changes. Depends on what your looking for.

 

[86SS86LS]

Yep 25% E85 and 75% gasoline sounds like the magic mixture, which makes me wonder why they didn't make E65 or something in that range.

We are starting to see blender pumps in our area where you can mix any % of Ethanol that you want. One of them is 45 miles away, I'm hoping that these become more common. I'd like to experiment with a 25/75 mix myself.

 

[ronbuick]

rmv, when you say disconnect the line going to the bottom of the fpr, you hook the hose to the fule rail tap port?? and no fuel will exit the bottom of the fpr, just wanting to clarify your statements, thanks.

Ron

 

[Jay Nesbitt]

No, you are measuring the volume of fuel bypassed (in excess of what is required to maintain rail press). This should be the quantity of fuel the system (pump+filter+lines) can supply at a given pressure/voltage/sg etc. It does ignore frictional losses in the rest of the return line, but as the fuel flow goes up, this loss would decresase.

I guess the best place to do this would be at the flex line just before it goes into the tank.

jn