Power with 91 octane

[fast rap]

from what iv came up with was true e-85 is equivalent to 96 octane.. I know for sure it's not 100+.

[fast507]

Ok, called my friend who is a fuel systems engineer with an aircraft company here locally. There are two types of octane ratings that apply here. Motor Octane, which is the fuel's resistance to Knock (detonate) in use as a motor fuel and the actual Chemical Octane Rating as defined by the R+M/2 (?) method which is a measure of a fuel's rate of burn. He said people quote the two very freely without understanding them, which is why there is such a spread in numbers. He also said the most common octane boosting additives are lead and alcohols which jives with what we see here.
He also said that octane rating found on most gas pumps are a MINIMUM standard and most fuels actually rate well above the number on the sticker.

[dsrules]

so i got to try out some e-85 in my quad... i had about 1gal gas in quad and then top off with e-85 drove it seemed a little better on top worse on the bottom so then i set my programmer from 3 on low rpm to 5 on low rpm... and from 5 on mid rpm to 6.5 on mid rpm top end left the same at 8...... tested again! now feeling better but still a little sluggush off bottom mid but better. so went back move low rpm to 8 and mid to 8 and top to 9.5..... tested again! this thing is making a huge inprovement with e-85. went back took my low to 10 my mid to 10 and top to 10.... tested again! boy did that really make a difference runs perfect top out on programmer with e-85.....and the power again a big inprovement all thruogh rpms.........when i ran straight gas on low rpm and set at 5 the quad would blow black out rear pipe now at 10 runs perfect no black at all and no backfiring and seams like my motor is running cooler now. when i finish with this tank i will try straight e-85 and post results. thanks everyone for information on e-85 I fill much smarter now! has any one else tried e-85 yet this stuff rips!

[fast507]

E-85 really shines when you start stuffing the fuel in there. The added O2 content from the Ethanol helps wake up the burn cycle. I've noticed that the MPG on my Tahoe drops with E10 as opposed to straight gas which makes sense with the added fuel demand.

[dsrules]

so now i got straight e-85 in my quad and the power on bottom all the way to top end is stronger than ever and runs awsome. i did notice it might start a bit harder only when engine is cold other than that thing runs great very nice improvement. fills like 2 or maybe 3 hp gain over straight gas. has anyone tried e-85 with pc-5 if so please reply thanks for input!

[LTMFB]

so you just went straight to E85 w/no dyno tuning? I'm not passing judgment, just genuinely asking...if so, i might give it a whirl!

[TNT]

Quote: Originally Posted by dsrules

so now i got straight e-85 in my quad and the power on bottom all the way to top end is stronger than ever and runs awsome. i did notice it might start a bit harder only when engine is cold other than that thing runs great very nice improvement. fills like 2 or maybe 3 hp gain over straight gas. has anyone tried e-85 with pc-5 if so please reply thanks for input!

Ours is hard to start cold too but once it starts if fires right up when hot. I often wondered if it is the E85 or big bore we run now I know. We have PC5.

[dsrules]

I started with about 50/50 ran out first tank and then moved to straight e-85 i would recomend a programmer with e 85. I have fmf goes to 100% add, with straight e-85 im guessing that a larger injector or a pc5 might be a good choice! tnt do you know what you have for injector size above stock and also what percent of increse are you adding to pc5 bottom to top end rpm? have you played around with settings for pc5 and e-85 thanks for your info!

[TNT]

We run the next bigger green injector, not sure what our dyno guy did to the AFR curve but we run a 50mm TB, huge FCI, and 495 so it will be different than yours.