Using Ethanol Fuel with FAST

[KTamez]

As of late in a 632ci BBC we've used a 20% mixture of Ethanol fuel along with C16 fuel. This has worked excellent, netting us an extra tenth, upping our carb jetting two sizes, to compensate the need for extra fuel....

My questions is how feasible/possible this would be in FAST Equipped EFI car... With Wideband 02, would the system compensate for the desired A/F Ratio, or is the Ethanol going to cause ill effects somewhere along the lines?

Would the Ethanol have adverse effects on the 02s themselves (Similar to Leaded fuel?)

Many thanx in advance.

Kurtis Tamez
www.LT4-396.com

 

[racer5039]

good question

I would like to do the same thing next year.
I am now using a 50pph inj. at about 78%.
I would like to do the change with out taking the motor out and dynoing it again.
Any body got any input.
I tryed to contact Wyoming Eth. but didn't have any luck.
thanks
Racer

 

[JDEstill]

I can't say I know for sure, but here's my educated guesses:

1. The ethanol shouldn't hurt the O2 sensor. Ethanol can be added to regular pump gas as an oxygenate (if California successfully gets rid of MTBE but still has to use an oxygenate, ethanol is one of the front runners). Since they couldn't do that if it was going to kill production car O2 sensors, I feel pretty confident it won't hurt the wide band O2.

2. I believe the system should compensate automatically if you have it in closed loop. It will still try to keep the a/f ratio that has been commanded. The question I would be asking is "Does the ideal a/f ratio change when the ethanol is added?" If you are running on straight gasoline and it needs 13:1 to make best power, with the ethanol added is the best ratio still 13:1, or is it now 13.5:1, or 12.5:1? If that changes then you'll have to modify the a/f ratio table to get it back to the optimum tune.

John

 

[Craig Smith]

I'll be switching to methanol soon, not ethanol, but I know for a fact that it works. The wide band will display a/f ratios assuming that it is gasoline being burned. So, if you see 12:1 a/f ratio being displayed on methanol, it's really more like 6:1. I don't know anything about ethanol, but I'll assume that it is similar to methanol in that you'll need about twice as much of it as compared to gasoline.

The alcohol setups I've seen so far seem to be setup for between 12 and 13 to 1 on naturally aspirated motors, so that part of it doesn't seem to be that different. I'm not sure if the VE table will need substantial modifications or not. I would guess that you could use your gasoline tuneup and play with the injector flow rate in the software and get it pretty close.

So, Kurtis, for you my answer is that yes, it can be done. I'd simply recommend a periodic visual inspection of the sensor for corrosion damage. Closed loop operation will help you get things close.

Racer, my suggestion for you if you go this route is to trade in your 50 lb/hr injectors for a set of 96 or 100 lb/hr injectors. I would simply swap the injectors without changing a single other thing and see if it is close.

Hopefully I'll have some personal experience soon to share with you. I have a motor going together right now. On the dyno, I'm going to fire it and tune it first on gas, and then switch to alcohol and see what happens. I'll post something here as soon as I do.

Craig

 

[AdioSS]

This is an old thread, but are there any new answers?

 

[AnArKey]

Ethanol's stoich AF ratio is 9:1, methanol is 6:1. If you switch to methanol from ethanol, you will need to richen it up.

As for what "displayed" AF to shoot for, you will still be safe at what you were before. But you might be able to make some more power by going a bit richer, as alcohol (methanol most of all) has a higher flammability limit.

 

[Craig Smith]

Originally posted by AdioSS
This is an old thread, but are there any new answers?

Yeah, I kicked the rods through the block on that motor while it was still on the dyno, but the alcohol worked great.

Methanol or ethanol works fine with this system. Many people doing it as per the guidelines discussed earlier in this thread. You will need to provide 50 to 75 percent more ethanol than gasoline by volume.

 

[bobc455]

Just so I understand...

If you want 12:1 on gasoline and switch to ethanol, could you switch to 96# injectors and tell the ECU that you have 48# injectors (or thereabouts)?

I'm also assuming that a standard injector won't have any problems handling ethanol?

-Bob Cunningham
bobc@gnttype.org

 

[Craig Smith]

You won't quite need to double it, Bob, but you are on the right track. You need about 50% more fuel by volume with ethanol.

The neat thing about ethanol is that it gives you many of the advantages of methanol without being corrosive. I have several customers who switched from methanol to ethanol for this very reason.

As near as I can tell, the problem with ethanol is finding it. I was really thinking about running it in my own race car but couldn't find a reasonable source for barrels of straight ethanol.