flex fuel octane in the 90's?

troyrod91 · 11-19-2009, 08:50 AM

i have a 2008 flex fuel and i was reading the manual and it only says use E85. but i know theres has to be a way to use a higher octane. does anyone know anything about this?

huffhuff · 11-19-2009, 08:54 AM

E85 is around 105 octane. 85 is the percent of alcohol in the fuel. You will get better mileage from the regular fuels out there.

Yahooligan · 11-19-2009, 09:03 AM

The octane is actually quite a bit less than 105. Think of it more as a super super unleaded, not as a racing fuel.

Quote:

Octane: A minimum octane for E85 is not specified. FFV’s
can tolerate the lower octane of gasoline i.e. 87 (R+M)/2.
There is no requirement to post octane on an E85 dispenser.
If a retailer chooses to post octane, they should be aware that
the often cited 105 octane is incorrect. This number was
derived by using ethanol’s blending octane value in gasoline.
This is not the proper way to calculate the octane of E85.
Ethanol’s true octane value should be used to calculate E85’s
octane value. This results in an octane range of 94-96 (R+M)/
2. These calculations have been confirmed by actual octane
engine tests.

sudden urge · 11-19-2009, 09:24 AM

E85 has an octane rating ranging from 100-105, making it a high performance fuel.

troyrod91 · 11-19-2009, 10:33 AM

i was just thinking about running a premium gas (from the pump) but i have flex fuel so idk how that would work? i think the premium is either 91 or 93.

desertruner09 · 11-19-2009, 10:47 AM

Quote:

Originally Posted by troyrod91

i have a 2008 flex fuel and i was reading the manual and it only says use E85. but i know theres has to be a way to use a higher octane. does anyone know anything about this?

Flex fuel vehicles mean that they are capable of running E85, not that you only have to use E85. So you can put 87,89 or 91 (or whatever you have where your at) and you'll be good to go.

troyrod91 · 11-19-2009, 10:49 AM

ok thanks for the help