jim lockwood

I read all that and, frankly, my eyes glazed over.

Neither article directly addressed how accurately a pump which is supposed to dispense E10 actually does so. That said, I'm reasonably confident that for an E10 pump, 10% ethanol is the upper limit of what the blend can contain by law (or EPA edict or whatever).

MikeM

The cheapest, easiest, fastest, most efficient way to cut the ills of the worlds environment is birth control.

Governments ain't up to the task!

FFBillysCor

Jim, you can check out several references on this issue. See Emerson or EMA (engine manufactures assoc), etc. A little knowledge and good fuel management will go a long way towards maintaining your classic. Best regards.

jim lockwood

I have done some looking. My take-aways:

1. E10, by law, may contain no more than 10% ethanol by weight.

2. Ethanol is not actually mandatory for California fuel. Only an oxygenate is required. Ethanol is used in CA to satisfy the oxygenate requirement.

3. The allowable Reid Vapor Pressure for CA fuels has declined from 9 PSI prior to 1992 to ~7 PSI for fuel available after 2007. Not sure what to make of this since I associate higher RVP with a greater tendency for there to be fuel perc.

4. There are approximately a gazzillion different fuel blends available in the US, depending on region. No wonder some people report issues and others give those folks the Internet equivalent of a blank stare:

US Gasoline Map

Anyway, back to point #1, 10% is the maximum amount of ethanol allowed by law in fuel sold as E10, just as I thought. If you have tangible evidence that the actual percentage sold is greater, feel free to post it.

Jim

BTW, my sources for the above information include the web pages of CARB, EPA, and ExxonMobile

biggd

I had a 55 Chevy about 7 years back with a 350 engine with 3 deuces. I had it for 5 years and it always ran like a top. The first year that they introduced the 10% ethanol and from my very first fill up it never ran the same. After one off season with that stuff sitting in the carbs they were junk. I pulled the carbs apart to rebuild them and the insides were so corroded that I decided to change it over to a new 4 barrel. Coincidence, I don't think so? I sold it a year later and bought a 67 Coupe project which has FI.

MikeM

The CSM link was simply to point out that there is/was a glut of alcohol on the market that the refiners had to pay for but couldn't use. Legally.

Legally being the operative word here.

I'd bet there is a healthy financial penalty for retail outlets if they're caught selling more that 10% in their tanks. They might even be leaving themselves open to a civil lawsuit.

If anyone is unsure what alky content they are getting, there are cheap little test kits that can tell you real quick what is going in their tank.

rtruman

Just went to a place that sells racing fuel ,I bought 2 gallons it was $8.50 gallon
I just wanted to see if it makes a difference .I have about 1/2 tank now was going to run some out first. I asked this guy what octane it was he said it was Sunoco 260 108 octane.
Heck I used to run that all the time is this plan gas or racing fuel. Thought racing fuel was different.

JohnZ

It does, but only if you change your tuneup to take advantage of the increased resistance to detonation it can provide (add more spark advance).

rtruman

Got ya