HarleyTechTalk

Dyno & Tuning Zone => AFR & Tuning Zone => Topic started by: VernDiesel on June 10, 2023, 11:18:54 AM

Title: 90 octane pure gas vs 93 octane with 10% ethanol
Post by: VernDiesel on June 10, 2023, 11:18:54 AM
Which do you think is better and why?
Makes more Power or better detonation resistance?
11.5-1 114ci M8
Title: Re: 90 octane pure gas vs 93 octane with 10% ethanol
Post by: JSD on June 11, 2023, 03:01:22 AM
Ethanol is harder on rubbers etc . But octane rules . Are you pinging at 11.5 on 93 ?
Title: Re: 90 octane pure gas vs 93 octane with 10% ethanol
Post by: VernDiesel on June 21, 2023, 11:22:12 PM
No just wondered what people thought was best and why.  I have access to both locally.
Title: Re: 90 octane pure gas vs 93 octane with 10% ethanol
Post by: wolf_59 on June 22, 2023, 05:07:04 AM
In my area we have 86 for regular and 91 for premium
I have tuned both my bikes to run on 86 one is set at 11.3 and the other is set at 10.5
I run 86 because it is available at every hole in the wall station where I have had trouble finding 91 in the past
Title: Re: 90 octane pure gas vs 93 octane with 10% ethanol
Post by: hrdtail78 on June 22, 2023, 02:54:00 PM
I'd rather tune for the 93.  I do wonder if the fuel is rated at 93 and then mixed or is it 93 calculated with mix? 
Title: Re: 90 octane pure gas vs 93 octane with 10% ethanol
Post by: billbuilds on July 15, 2023, 02:54:44 AM
     I'm thinking that octane would have to be figured in after ethanol is added. Just found a piece that explains  some of it. I too would want to run the higher octane blend. ethanol and octane explained (https://mnbiofuels.org/media-mba/blog/item/1511-octane-and-ethanol-for-beginners#:~:text=When%20you%20mix%2010%20percent%20113%20octane%20ethanol,octane%20and%20E85%20%2885%25%20ethanol%29%20is%20108%20octane.)