Ethanol in Fuel

[GoFast1965]

Quick question for the group. Do you run ethanol free gas or does it matter. This would be for a 427 ERA with a 427 FE Shelby aluminum block and aluminum heads, normally aspirated and carborated car. In my area I can find ethanol free 90 octane, but cannot find ethanol free 93 octane around. Your expertise and experiences are much appreciated.

[Tommy]

Consider this one data point. I've been running 93 octane E10 gas in my carbureted hotrods since it came out without any obvious problems. I can't say the same for my garden equipment. I suspect the difference is that I run my cars often enough to avoid "old gas" problems.

[1985 CCX]

Works ok, Race Fuel is 10x better. I am lucky as Cam2 is pump gas here in NH.

[Grubby]

We just drove my ERA from Indianapolis to Monterey and back - 6,000 miles. The car now has 10,200 on it.

Given the choice, I will always buy alcohol free. The only short term issue I see is dieseling on some shut downs.

I have found that using a half can of Lucas Octane booster with 90-93 octane and the car runs and shuts off perfectly. Yea, the carb my not last 100,000 miles, but what can you do.

427 side oiler, built by Lykin's Motorsports.

John

[twobjshelbys]

Originally Posted by 1985 CCX

Works ok, Race Fuel is 10x better. I am lucky as Cam2 is pump gas here in NH.

Unless your engine is specifically built for the high octane you're just throwing money away.

If you buy an engine that requires 110 octane race fuel and you don't race your car almost exclusively, you should seriously reconsider your purchase.

Yes, cars with a 10.5:1 engine run just fine on 91 octane E10.

Note: 93 vs 91 depends on location, higher altitudes uniformly lower the standard octane ratings by 2 points

The whole thing about what the interchangeability rules for E10, E15 and E85 are based on fact and folklore... Several references say E15 should only be used in E85 flex fuel engines, while others claim that E10 and E15 are 100% interchangeable. For sure E10 and E85 are NOT interchangeable and some aftermarket tuners provide race tunes for E85.

[Daytona Dek]

Here in the U.K. we’ve changed from E5 (5% ethanol) to E10 (10%} although E5 is still available but not at all garages. I was under the impression although E10 might affect engine performance/economy it wouldn’t damage it. It would, however, affect rubber seals in carbs etc. Found this on Hagerty:

What’s the problem for classic cars?
Although many cars run on E5 without significant problems, doubling the amount of ethanol in the fuel can cause a variety of issues in olders cars. Ethanol is hygroscopic, which means that it absorbs water from the atmosphere. And that water, in turn, finds its way into your car. It can lead to condensation in fuel tanks, fuel lines and carburettors and cause corrosion in brass, copper, lead, tin and zinc components.
As ethanol is also a solvent it can eat through rubber, plastic and fibreglass, so hoses and seals are likely to perish more quickly because of the higher concentration of ethanol in E10. In Department for Transport tests, problems identified included degradation to fuel hoses and seals, blocked fuel filters, damaged fuel pumps, corroded carbs, blocked injectors and corrosion in fuel tanks. Rubber is particularly affected. The Federation of British Historic Vehicle Clubs (FBHVC) has a list of ethanol-friendly materials that can be used as replacements.
Finally, ethanol isn’t as energy dense as petrol, which means that the fuel-air mix could be leaner and, ironically, fuel consumption could actually be slightly higher than using E5 or ‘pure’ petrol

[Tommy]

The Engine Masters TV series did a whole show testing different octane fuels on the dyno. There was no noticeable difference in the torque/power numbers between them even when the timing was adjusted to optimum. The only benefit of higher octane was knock/ping resistance. So, according to them, if the engine is not knocking/pinging when you use it, higher octane fuel is pointless.

[Bartruff1]

There is non ethanol fuel available locally.....and that is what I use for my engines that are not used daily......I had to replace the fuel system in a boat and that was enough for me....a cat that sits on a hot stove....will not sit on a cold stove....

[CompFi]

Originally Posted by Bartruff1

..I had to replace the fuel system in a boat and that was enough for me.....

Same for me.

My daily driver (Jeep) gets typical pump gas.

Everything else, gets ethanol-free. I will gladly pay the $1 / gal markup to mitigate headaches from ethanol.