U
Uncle Ben
It has been three months now since I converted my 1999 OBW to flex-
fuel.
MPG=miles/gallon, MPD=miles/dollar
Suburban MPG E10: 25, E85: 21
Highway MPG E10:28, E85:24
Suburban MPD E10: 6.2, E85: 7.0
Highway MPD E10:7.0, E85:8.0
I have no way to measure horsepower or torque, but on E85 I have the
ability to pass and to make a needed acceleration boost that is simply
not available on E10. Saab has test data on one of their sportier cars
with flex-fuel that confirms an improvement between 10% and 20% in
both HP and torque.
There was a period of trouble with the MIL coming on with code "Long-
term Trim" showing too lean. That was because I tried too quickly to
improve MPG by adjusting the amount of stretch in the pulse to the
fuel injectors, as an experiment. The computer ECU took a long time
to readjust the trim and never really found a better value.
I had to add back some gasoline to find what the car was asking for in
trim. Then I changed to higher concentrations of ethanol gradually,
checking the trim as I went along with my trusty scanner, making sure
that the short-term trim was properly moving the long-term trim in the
right direction. Finally I am back to E85 with no MIL.
I should have left the job to the ECU in the first place, and I would
have had no trouble at all.
Bottom line: For E85 prices in NY being consistently 25% lower than
E10, and for the Subaru car having a smarter ECU than the Chevrolet
Tahoe (which suffers a 34% penalty in MPG on E85),
fuel.
MPG=miles/gallon, MPD=miles/dollar
Suburban MPG E10: 25, E85: 21
Highway MPG E10:28, E85:24
Suburban MPD E10: 6.2, E85: 7.0
Highway MPD E10:7.0, E85:8.0
I have no way to measure horsepower or torque, but on E85 I have the
ability to pass and to make a needed acceleration boost that is simply
not available on E10. Saab has test data on one of their sportier cars
with flex-fuel that confirms an improvement between 10% and 20% in
both HP and torque.
There was a period of trouble with the MIL coming on with code "Long-
term Trim" showing too lean. That was because I tried too quickly to
improve MPG by adjusting the amount of stretch in the pulse to the
fuel injectors, as an experiment. The computer ECU took a long time
to readjust the trim and never really found a better value.
I had to add back some gasoline to find what the car was asking for in
trim. Then I changed to higher concentrations of ethanol gradually,
checking the trim as I went along with my trusty scanner, making sure
that the short-term trim was properly moving the long-term trim in the
right direction. Finally I am back to E85 with no MIL.
I should have left the job to the ECU in the first place, and I would
have had no trouble at all.
Bottom line: For E85 prices in NY being consistently 25% lower than
E10, and for the Subaru car having a smarter ECU than the Chevrolet
Tahoe (which suffers a 34% penalty in MPG on E85),