Fuel Names


In the 50’s there use to be only 2 grades of gasoline. Regular and Ethel (sometimes called High Test)I have also heard the term tetra-ethel-lead, but I see that as only a valve coating additive, in the days when all gasoline was leaded, not an octaine booster. Was there ever Ethanol in the early ethel gas to boost octaine or were there other lighter petroleum distilates added for that purpose?

If not where did the term come from or what does it mean? Thanks


Wasn’t Ethyl the commercial name for leaded gas? It doesn’t have anything to do with ethanol if you were confused because the names sound similar. Tetraethyl lead (TEL) was added to gasoline to reduce engine knock. They tried all sorts of additives before coming up with lead.

I can’t answer your other questions.


In the old days, the octane of regular gasoline was boosted by adding tetraethyl lead. Such gasoline was called premium, ethyl, hi-test, super, etc. All the same.

Ethanol (ethyl alcohol) is not an octane booster. It may have been added to '50s gasoline in small amounts for winter formulations. It’s sole purpose would have been to deal with any moisture in the fuel system.


You are confused about what they used to put in gasoline in the past to BOOST THE OCTANE. That WAS tetraethyl lead, and it was used until the environmental phase out in the seventies and replaced with other octane boosters that do not contain lead. Initially, only high test gas contained it, hence the name “ethyl” for high test.

Tetraethyl lead was by far the cheapest way to boost octane ratings and it was used with varying degrees. Its phase-out was fought tooth and nail by lead procucers.

Of course, catalytic cracking produced more gasoline from a barrel of oil, but to accommodate high compression engines, you needed and additive.

MTBE was a good additive, but it was so durable (stable) it contaminated ground water and California was the first jurisdiction to ban it.


Yes, lead was added in varying amounts to all gasoline in the old days–both high test and regular. The high test had a lot more lead; it was a costly additive. One company added refining steps and produced a gasoline with the required octane rating without adding lead(Amco). The lead did lubricate the valve guides and helped to seal the valves themselves. In the 1970’s the auto companies asked the oil companies to produce lead-free gasoline so catalytic converters could be installed (about 1975). The trade-off was that the octane dropped in the unleaded gas to the level it is today. In the old days the octane was much higher-sometimes in the mid to high 90’s.


The octane rating for leaded regular was 89 in 1973 when I started pumping gas for a living. This was using the current formula (the average of Research and Motor octane ratings). Sometimes, stations back then would report only the Research Octane Number, which could be 8 to 10 points higher than the Motor Octane Number.


MTBE does not contaminate ground water. Leaking underground tanks contaminate ground water.


The problem with MTBE is it DOESN’T evaporate or break down easily. So when it gets in the ground water it stays there. Ethanol DOES evaporate and break down. So there is less chance of your drinking water getting contaminated.


I would not mind it a bit if my drinking water were contaminated with sizable quantities of ethanol.


Everyone’s right. Like Beadsandbeads said, leaking tanks are the contributing factor to the pollution of groundwater. Better government regulation is limiting leaking tanks, but the people that run some of these places are so uninformed that they’ll always be a problem (which is almost good, because I fix these problems for a living!).

Like Docnick and MikeInNH said, MTBE is terrible because it’s very soluble and doesn’t break down easily. It does a great job preventing knock, but it’s ruining groundwater supplies.

I love my gasoline-powered car as much as the next person, but sometimes I wonder about our improvements. Lead was a serious problem as an additive because it led to high concentrations of lead in the environment, not to mention developmental problems in children and cases of lead poisoning. So we replaced it with MTBE, which is polluting our groundwater aquifers and we’re running out of fresh water. What’ll be next? We’re running out of oil anyway so the new additive almost doesn’t matter. What we need is either an econmical, sustainable alternative fuel or to completely overhaul and expand our public transportation infrastructure and change our way of life. It’s going to be rough going either way.