90 No Ethanol vs 93?

[Cincinnatus]

Howdy, folks!

I recently found out that a nearby Sunoco station has 90 No Ethanol fuel. I normally fill with 93 which contains up to 10% Ethanol, so I was wondering if you could share your opinion on which is better, and why.

Thanks!

[TinCanSailor]

10% ethanol has an efficiency loss of about 3% mpg. That close of a difference in octane rating may not produce many noticeable knock or pre-detination issues if you are not hammering the car. Ethanol is hygroscopic which means it will hold/retain water and if allowed to sit too long could result in rust. That said most modern cars are now engineered to deal with the issues that the introduction of alcohol caused in earlier cars, rubber and plastic components didn't fair to well against the alcohol.

I prefer to use it when I can find it 90 or higher. I live in Florida so boaters use it a lot to help preserve their boats and rec vehicles. Some marinas here will sell 93 but usually only to boaters.

I have motorcycles and classic cars so I use ethanol free a lot. Here is a good site and application for finding ethanol free gas if you decide to use it more.

https://www.pure-gas.org/about

[Cincinnatus]

Thanks for that. Would it be worthwhile to run even just one tank full through to 'clean it out' or is there no preventative benefit to be had?

[TinCanSailor]

Originally Posted by Cincinnatus

Thanks for that. Would it be worthwhile to run even just one tank full through to 'clean it out' or is there no preventative benefit to be had?

NO real preventative benefit in pure gas really. Run something from a tier 1 gas company that has an additive already. That said if you are driving a car with direct injection you will only get a partial benefit to cleaning. The issue with DI is that gases are return to the intake valves and since DI doesn't spray on that valve there is no cleanup taking place.