Technical Discussion Topics related to Technical Issues

ethanol effect on AFR ??

Thread Tools
 
Search this Thread
 
Old 03-13-2011 | 06:42 PM
  #1  
mortbike's Avatar
Thread Starter
Member
Squid
 
Joined: Jun 2010
Posts: 97
From: Coral Springs, Florida
mortbike is on a distinguished road
ethanol effect on AFR ??

I have tuned my VTR to run on 87 octane with 10% or less ethanol.
I have found a gas station nearby that sells 90 REC non-ethanol gas.
Will using the non-ethanol free fuel make my AFR richer or leaner? thanks-Mort
Old 03-13-2011 | 06:55 PM
  #2  
xeris's Avatar
Senior Member
SuperBike
 
Joined: Sep 2010
Posts: 1,926
From: Bisbee, AZ
xeris is on a distinguished road
I'm sure that someone will correct me if I'm wrong.
The higher octane fuel will act like the tune is slightly richer.
Old 03-13-2011 | 07:25 PM
  #3  
VTRsurfer's Avatar
Senior Member
MotoGP
 
Joined: May 2008
Posts: 3,451
From: San Clemente, CA
VTRsurfer is on a distinguished road
Air/fuel ratio is just that... air and fuel. Ethanol is fuel.
Old 03-13-2011 | 08:44 PM
  #4  
Stevebis1's Avatar
Senior Member
SuperSport
 
Joined: Sep 2008
Posts: 805
From: Delmar NY
Stevebis1 is on a distinguished road
Originally Posted by VTRsurfer
Air/fuel ratio is just that... air and fuel. Ethanol is fuel.
While literally true I'm assuming the question is is really asking about the affect on the carb tuning.
E90 needs a slightly lower (richer) stiocheometric ratio to work best. In most vehicles not enough to be noticeable, but in our Shawks, depending on your current state of tune and how sensitive you are, it can be.
Personally I could feel the difference, especially when I was running the K&N. With that filter I had a slight lean stumble at 2800 rpm. when filling with straight up gas that stumble would pretty much go away.
Ethanol has been a hot and disputed topic here in the past, but I'm on the side that says there is a difference.
Old 03-15-2011 | 07:53 PM
  #5  
JamieDaugherty's Avatar
Senior Member
SuperBike
 
Joined: Aug 2005
Posts: 1,858
From: Fort Wayne, IN
JamieDaugherty is on a distinguished road
As mentioned, Ethanol requires more fuel to reach the proper stoichiometic levels. Normally this is only a problem for those karate-car dudes running the E85 conversions. At E10 or E15 I doubt there is enough "E" to throw off your mixture.

Bottom line - just run the non-E gas and enjoy.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
tbartley
General Discussion
14
01-11-2010 11:21 PM
mwdejager
General Discussion
2
03-27-2009 08:35 AM
J.J.
General Discussion
8
11-06-2006 04:55 PM
consumer
Technical Discussion
4
12-21-2005 02:12 PM




All times are GMT -7. The time now is 04:10 PM.