cant decide which to use, anyone have any preferences?

 

Care to elaborate on your application?

 

For a stock head and block N/A car, E85 will do nothing except hurt fuel economy (a lot).

For a turbo motor, however, it's a revelation.

In my 2005 Evo I jumped from 300whp to 347whp doing nothing but changing from 100octane to E85 (bigger fuel injectors also required). Fuel economy dropped about 25%.

 

Agreed with Cracknut. E85 is rated at 113 octane, allowing you to advance timing reliably and yield an increase in HP. I am somewhat convinced that the cooling properties of E85 during combustion are a major contributor to why we are seeing more reliable turbo time attack and race cars (see Momentum and the FI boards).

If you aren't FI'd...you can achieve those octane levels running race fuel without seriously compromising fuel economy...but you'll still need to advance your timing to take advantage of the higher octane fuel and make more power.

Good luck!

 

supercharged, 1000cc injectors, kpro, currently tuned on e85 making 444whp

 

Juan, so you're currently supercharged and running E85? Why would you switch? Do you track the car?

Why would you switch back from that fuel when you're making 444whp reliably with a supercharger? Seems like a step in the wrong direction.

 

It's all about whether or not your plan on bringing a drum to the track with you.

-Rob

 

hehe...Amen. That's why i run 100 octane. hehe

 

I dont know if this applies everywhere, but at the few stations around here that offer e85, it seems different EVERY time i filled up.

I had to retune the car every time. That got old fast.

 

yeah I run 110 leaded so I don't have to bring a drum of fuel with me. I like knowing that every track will have the fuel I need.

Also some orgs (such as SCCA) still don't officially allow e85 (old rules, supposed to change soon)