ShaneM

So the EPA is set to approve a 15% ethanol blend and they are expecting it to replace 10% blends in most areas by the summer. if ethanol is used in my area was one of the things that VMP asked me to write my tune. So if my local station ditches the 10% blend and goes 15% will I need a new tune?

http://www.autonews.com/apps/pbcs.dl...303109841/1186

kgrun4

I had no idea this was in the works, thanks for pointing this out.

ShaneM

on further reading after i asked this, the fuel is approved they are simply waiting on the labels to be finalized. They are saying the fuel will be good for all gas vehicles from 2001 up. hopefully it wont be something bad for those of us on non-factory tunes. i would hate to think I will have to buy a new tune. I assume if the octane is the same it will be good, but i am not sure.

Nuke

As it stands now, I've seen my fuel mileage affected by as much as 4 MPG going from "straight" fuel to 10% (or more) ethanol. Performance WILL also suffer.

I'd like to hear from the AM and Brenspeed folks that post on the forum if they can do anything to conteract any performance issues.

ShaneM

i also asked justin at VMP about this, nothing back yet.

LostBoyz

I wouldn't touch the stuff, considering every OEM and many other manufacturers are currently together in fighting the legislation. I think they know more about their product than the EPA or congress does.

ShaneM

the problem as i read it is that it will replace most of the current 10% blend since the station would have to either install a new tank to hold the 15% blend or some sort of mixing pumps to reach 15%. i don't see stations carrying both and i think most will go for the cheaper stuff.

BlackBetty

I would see the number one tune concern being the possibility of a different octane rating with E15. E15 will have the same octane as E10 blends... the oil companies will just use lower octane gasoline to compensate for the increased octane from the ethanol.

My guess is that the oil companies will offer both E10 and E15 at first and slowly phase out the E10. As you said Shane, the stores would have to have separate tanks for the two products and that is hugely expensive. If some stores start selling E15, the rest will follow.

DreamerGT

http://www.autoblog.com/2011/02/22/r...lock-e15-fuel/

ShaneM

the story link i posted is newer than Dreamers and shows that its basically a done deal. i have no idea where these places get their info, but it seems the issue is moving forward again. anyway, this is what Justin said:

It basically hurts everyone…

Fuel economy goes down, because of the lower energy content in the ethanol.

If you have a turbocharged or supercharge vehicle with high fuel demands at WOT, it will push your injector and fuel pump duty cycles higher.

Having more ethanol in the gas makes tuning cars more difficult and more inconsistent. The ethanol level in the gasonline is not always held at a full 15%. It can be all over the place from one fillup to the next. If your car is tuned with a wideband while running 15% ethanol, and then you run fuel with no ethanol in it, you’re air to fuel ratio can shift over a point richer. This is huge from a tuning standpoint in terms of power and efficiency. The OEMs have realized this and most 2011+ Fords including the Mustang GT and Shelby GT500 use widebands from the factory. These vehicles are closed loop at WOT (wide open throttle) and are constantly correcting air/fuel ratio at all operating conditions. The PCM keeps the actual A/F and the commanded A/F the same, this is great for performance, efficiency, reliability, and safety.