sketchers356

What does it do? Where to install?

I am sure the answer is somewhere in the A-tune thread but it is 25 pages long and largely on the M-tune.

zerMATT951

This post in the M-Tune thread shows in in the DME harness. Install the jumper for the secondary map, remove for primary. From the factory, the jumper is pre-installed.

https://rennlist.com/forums/8893950-post173.html

Rogue_Ant

The Jumper switches between pump fuel and race fuel:
Jumper off = pump fuel
Jumper on = race fuel

See here for jumper location:

sketchers356

Great thanks Josh! What is the definition of Race fuel?

Rogue_Ant

100+ octane.

Scott H

Where does E85 usually come in on the octane scale?

Turbodan

my guess is the 85 is the octane e is ethanol added.

sketchers356

Kinda a different subject but E85 is 85 percent ethanol 15 percent gasoline. It has an motor octane rating of approximately 97 I believe. Since it does not have the same energy density as gasoline it needs a whole different tune and is quite different than race gas.

zerMATT951

E85 octane is typically between 100-105, with some claims between 105-113.

Rogue_Ant

There is some conflicting info, but in my experience, E85 acts like at least 105 octane. The cooling affect of the alcohol makes it act like a higher octane than what some ratings suggests.

schip43

Yep my understanding is that it's well over 100 octane.

sketchers356

These figures are miscalculated from what I hear. Wikipedia claims 94-96 with a reference by the renewable fuels foundation stating that there is a difference between the higher blending figure and the R+M/2 octane.

sketchers356

Sorry that I do not have the experience.

Rogue_Ant

Yep - after running E85, then I do not like going back to gas... Even without the increased performance, the added safety is reason enough for me.