E85?

[Mandi90TT]

Can I just put E85 in to increase octane? If so, what's the optimal mix if the base fuel is CA 91?

[Mandi90TT]

Anyone have any thoughts on this?

[DREW@SUPREMEPOWER]

I am assuming that your not running any tune or piggyback on the car? If not 100 octane is your best bet.

[EdgeCrusher]

Have to have a piggy back like JB4 or dont even run it..... better to use 100 oct if your stock.

[AM4ZING]

Originally Posted by EdgeCrusher

Have to have a piggy back like JB4 or dont even run it..... better to use 100 oct if your stock.

I have the JB4 and have tried e85 twice...

1st time i added 3 gallons in a full tank, switched over to MAP 2 and the car felt noticeably faster. Turbo spool was immediate and i couldn't keep the tires from spinning

2nd time i added 4 gallons in a full tank, though it pulled harder than 3 gallons, i noticed some bogging, cutting out around 5-6k RPM

My impression was that about 3-3.5 gallons is perfect. Although each car and circumstance is different

Bottom line, I LOVE E85!!

[Myaddiction]

You can put in 1 gallon in a stock car. The factory DME can support it via fuel trims. Though you should datalog the trims to make sure its ok.
It won't make much of a difference power wise unless you are running 91 octane. It'll help you get up to the same level as 93.

JB4 is the only way to be able to switch between fuels. Some of the flashes will flash your car for a E85 mix but your stuck with that till you reflash for another fuel.

Once you run E85 you'll hate putting pump gas back in it. It's not even close.

[Fast4d]

my car is 100% oem right now.

added 4 gallons then topped up with 91 (91 is our premium unleaded).

made a bunch of pulls at highway speeds and butt dyno says more power.

but I think I maybe playing with fire. good thing it has been warm so air is not as dense.

will stop using E85 until I get JB4 setup.

will try mixing in 100 unleaded next time.

[Mandi90TT]

ESS flash tune from EAS (for 91 octane ). Would like to get the octane up and E85 is easier to get than 100 octane (and cheaper). Also wonder if Amsoil Octane Boost would do the same thing. Used to use the Amsoil all the time during my track days as kind of a safety net

[tom @ eas]

Originally Posted by Dave 90TT

ESS flash tune from EAS (for 91 octane ). Would like to get the octane up and E85 is easier to get than 100 octane (and cheaper). Also wonder if Amsoil Octane Boost would do the same thing. Used to use the Amsoil all the time during my track days as kind of a safety net

You can get away with a gallon or two of E85 in a full tank, it's best to run some race fuel mixed in to bump up the octane. Some 76 stations offer 100 octane at the pump, search in your area.

An alternative would be to keep a bottle of Torco Accellerator octane booster in the trunk, we do this as a backup at the track in case the pumps are down.

[EdgeCrusher]

Originally Posted by AM4ZING

I have the JB4 and have tried e85 twice...

1st time i added 3 gallons in a full tank, switched over to MAP 2 and the car felt noticeably faster. Turbo spool was immediate and i couldn't keep the tires from spinning

2nd time i added 4 gallons in a full tank, though it pulled harder than 3 gallons, i noticed some bogging, cutting out around 5-6k RPM

My impression was that about 3-3.5 gallons is perfect. Although each car and circumstance is different

Bottom line, I LOVE E85!!

Id say your assessment is correct! I just did a dyno and the mixture has to be pretty close to notice a difference