Alright I currently have my car tuned for e85 right now, and that’s all it runs on. I hear people being able to switch between maps for e85 and regular pump gas, my ques. Is how are you guys doing this? What software or engine management tool are you using? Also, isn't it dangerous? For example, k, say I have e85 in my tank right now and I want to switch over to a 91oct map, would I have to drive until the e85 is completely drained out of my gas tank or would I have to drop the tank and suck the e85 and pump regular gas back in and load the map? Or would you drive it near empty and just fill it with pump gas, but the problem with this is, would you know when the tank is empty enough to fill in pump gas? I m still a newbie at this, so sorry for all the questions. I will be getting a BBK turbo soon here and I'd like to have it tuned for E85 but there is only 1 e85 station where I live, so I'd like to do some traveling with my evo and not have to worry about finding a e85pump.

 

alt map harness

it is a pre-fabbed harness that get wired into the ecu and can switch between maps at the push of a button

look them up in the ecuflash section

 

there's also the tephra V7 that allows you to switch via the TPS sensor.

 

to answer the run outta gas question then yes you have to basically run outta gas till the car stalls, then fill up on your 91 and switch the flip over... thats how ive done it

 

doesn't that burn out the fuel pump over time?

 

^+1 i think thatd be more dangerous. why not just run one then drain it if your getting close to empty, and refuel.

 

impossible.

 

Yes, it will burn the fuel pump out over time if they let it run dry until it stalls. You should just run it down to under 1/4 a tank and then fill up on 91/93. It will take a tank to run all of the ethanol out of the system, but it will be just fine. Get an ethanol gauge if you are really worried. Then you know what the mix is getting sprayed in at that moment.

Here is an example of an alt map from BR: https://secure.buschurracing.com/cat...57f65ba58cf79b

 

so u will need 4 maps total? one for e85, one for e85/mix with a 1/4 of regular gas, and another one for just 91pump gas? and one for 1/4 tank of e85 mix with 91? am I right?

 

not...you can run either map with a 1/4 tank of the opposite fuel

however I'd be more careful to not rip on the car

 

ok question on this:

i dont like the whole running it dry b/c as much as it does get rid of all the fuel i dont really wanna burn out my fuel pump lol.

i like the whole running it low then filling it with the opposite gas. I just wanted to clarify is how long til that other gas is burned out of the system.

Right now im on 94 octane and i wanna get it outta my system cause im gonna be doing 91 octane + meth. Im doing it for the same reason the OP is. i wanna be able to travel in my car and not be restricted to this gas. i was told meth is awesome cause u can bring it with u and it triggers when u need it ... best of both worlds