Ethanol Effects
#1
08-16-2008, 10:01 PM
Join Date: Nov 2007
Posts: 267
Likes: 0
Received 0 Likes
on
0 Posts
Ethanol Effects
Now that we're being forced to run ethanol-laced fuel in our trucks, I'm just curious as to any effects this stuff has on our valves and seats after many miles. Has anyone yanked a set of heads after 100k miles of ethanol, and how do they compare to a like mileage set run on non-ethanol? Any unusual deposits? Besides the lower fuel economy, is this something else we should be concerned with regarding ethanol?
#2
08-16-2008, 10:04 PM
Senior User
Join Date: Jun 2003
Location: Memphis
Posts: 225
Likes: 0
Received 0 Likes
on
0 Posts
Below is a quote from the SVTOA Memphis thread about ethanol. I know that what he has to say is geared towards performance cars but it should provide some insight into local experiences with Ethanol and tuning.
This is what I have found out doing some research for vehicle's running 10% ethanol in their fuel.
93 Octane (no ethanol) stoich air/fuel ratio is 14.64. This is perfect air fuel at idle and part throttle. Wide open throttle air/fuel for your vehicle should be between 12.8 - 13.2. This is for a bolt on vehicle without heavy engine modifications.
93 Octane (with 10% ethanol) stoich air/fuel ratio is 14.1. When ethanol is added to the gasoline, you will have to run about 5% richer in the tune. Wide open air/fuel ratio should be 12.3 - 12.7. This is for a bolt on vehicle without heavy engine modifications.
93 Octane (no ethanol) stoich air/fuel ratio is 14.64. This is perfect air fuel at idle and part throttle. Wide open throttle air/fuel for your vehicle should be between 12.8 - 13.2. This is for a bolt on vehicle without heavy engine modifications.
93 Octane (with 10% ethanol) stoich air/fuel ratio is 14.1. When ethanol is added to the gasoline, you will have to run about 5% richer in the tune. Wide open air/fuel ratio should be 12.3 - 12.7. This is for a bolt on vehicle without heavy engine modifications.
#3
08-16-2008, 10:42 PM
Join Date: Nov 2007
Posts: 267
Likes: 0
Received 0 Likes
on
0 Posts
Well that would seem to suggest the richer mixture required for running ethanol would leave more deposits, unless the ethanol helps the A/F mixture burn more completely. Which brings up another question... If ethanol leaves more deposits, could that be a contributing factor (other than the poor design ) to the 5.4 plug breakage issue?
#4
08-16-2008, 10:45 PM
Senior User
Join Date: Jun 2003
Location: Memphis
Posts: 225
Likes: 0
Received 0 Likes
on
0 Posts
#5
08-16-2008, 10:58 PM
Join Date: Nov 2007
Posts: 267
Likes: 0
Received 0 Likes
on
0 Posts
10% ethanol is in almost all brands of gas, Flex Fuel is E-85, I believe.
#7
08-17-2008, 12:47 AM
