History of Fuel Octane ! O the good old days !

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: History of Fuel Octane! O the good old days!
30th-November-2010, 05:21 PM
What are the major differences between the gas sold back in the 60’s and modern fuel. Was there a difference in octane? I was thinking about putting plus in my car (89 octane) because it might be closer to what the car ran on back in the day as it has the original inline maybe run a little smoother or should I stick with 87?. I know that the lead acted as an octane booster as well as a valve stem lubricant.. Thoughts suggestions?

30th-November-2010, 07:33 PM
oh how I dream of the days of pink gasoline.:turn: It use to make everything run better. It was higher octane,and it did have lead…But you could go to Union 76 and your car/morotcycle ran like the wind, with the pink gasoline.:D
30th-November-2010, 08:21 PM
Remember these?http://www.tommcmahon.net/2010/08/sunoco-blendomatic-gas-pump.html
The Big Al
30th-November-2010, 08:46 PM
The History of Gasoline Octane

As the high compression engine era was gaining steam in Detroit during the early to mid 1950s, the need for higher octane gasolines was becoming more and more apparent. When automobile production resumed in 1946 following World War II, gasoline octanes in the United States averaged at 79 for regular and 85 for premium and those numbers climbed year after year until 1954, when premium gasolines were rated as high as 94 octane and regular at 86. Oil companies were promoting their gasolines, especially their premium grades, with claims that their fuels increased power and gas mileage while cleaning out the carburetor and other engine parts to wash away accumulated carbon and other deposits while regular usage prevented the future buildup of such. Among the additives widely promoted by leading oil companies were Texaco Sky Chief with Petrox, Super Shell with TCP, Mobilgas Special with a Double Compound ingredient and Sinclair’s Power-X featuring a nickel additive.

As Detroit continued the horsepower race unabated in the mid-to-late 1950s, the oil industry responded by continuing to increase the octanes of their gasolines, and a few even went the extra mile by introducing “super-premium” fuels which were even higher in octane that the premium grades. In 1956, Sunoco introduced its “Dial A Grade” blending pumps that could dispense five different grades of gasoline, later increasing to eight, ranging from subregular Sunoco 190 to superpremium Sunoco 260. That very same year, Esso introduced a third grade of fuel called Golden Esso Extra, which came in a gold pump and had an octane rating of just over 100. That was followed in the spring of 1957 by Gulf, which introduced its super-duper Gulf Crest that was dispensed from a purple pump, and Chevron debuted its Custom Supreme grade in the western states.

By 1958, oil companies generally took a position concerning the number of gasoline grades offered with the greatest majority choosing to stick to just two (regular and premium) and simply increasing the octane ratings of both grades of gas with the premium fuels coming very close in octane to the super-premiums offered by some competitors. That year, regular gas averaged at about 90 octane and premium hit the 98-99 mark. With compression ratios on Detroit’s hottest engines reaching the 10 to 1 plateau and higher, nearly half of all 1958 automobiles were powered by engines requiring premium fuel. And that included virtually all medium and higher-priced automobiles, leaving only a few lower priced cars powered by engines capable of using regular fuel including most Ramblers and Studebakers, as well as Ford, Chevrolets and Plymouths with standard six-cylinder or small V8 engines.

But the advent of smaller compact cars with more economical engines, both domestic and foreign, along with detuned engines in some larger cars, slowed down the octane race a bit and by 1961 only one-fifth of new cars were powered by engines that required premium or super-premium gasolines. Motor Trend magazine noted the trend toward economy that year by pointing out that Chrysler Corporation had reduced compression ratios across the board on standard engines to burn regular gas, a move that may reduce miles per gallon fractionally but give you more miles per dollar. “Five years ago, new car buyers swallowed premium gas as a necessary evil; today a salesman has to have a good reason for specifying it.”

With a smaller proportion of new vehicles on the road requiring high-octane gasolines and the octane ratings of both regular and premium grades continuing to climb, demand for the more expensive super-premium grades, never really that high, dropped dramatically. In the fall of 1961, Esso and Gulf both discontinued their super-premium grades of fuel in favor of lower octane fuels to supplement their regular and premium offerings. Esso increase the octane of its premium Esso Extra and introduced a new middle grade of gas, Esso Plus, which was inserted in price and octane rating between Extra and their regular fuel. Gulf took a different direction by replacing its super-premium Gulf Crest with a new sub-regular product, Gulftane, which was priced about one or two cents less than its Good Gulf regular – and also designed for vehicles that could use gasolines with octane requirements lower than regular grades. In the process, Gulf created a subregular product that was priced on par with regular gasolines offered by cut-rate independent gas stations that generally sold gas for a few pennies less than major-brand stations – sparking off “gas wars” in many areas of the country where prices often dropped as low as 18 cents per gallon for regular and subregular grades (compared to the prevailing normal regular fuel price of 25-26 cents per gallon).

As the subregular and middle grades of gas came to market in 1962, the average octanes of gasolines in the U.S. now stood at 93 for regular, 99 for premium and 102 for the few super-premiums still left on the market. Those numbers would increase only slightly in the next few years to around 94 octane for regular, and 100 for premium by 1967.

By this time, other oil companies jumped on Sunoco’s bandwagon by offering blending pumps dispensing several grades of gasoline from one pump to tailor fuels to a particular vehicle’s octane requirement. Signal Oil Co. offered seven different grades of gasoline through its blending pumps at its Hancock and Norwalk stations in the Western United States. In the Mid-Continent region, Conoco began testing four-grade blending pumps in some markets in 1965 and introduced the concept throughout its marketing area two years later. In addition to Regular and Premium, Conoco offered its sub-regular Conotane (similar to Gulftane) and a Super grade between Regular and Premium similar to Esso Plus. A similar four-grade pump setup was offered by Skelly that included Skeltane (sub-regular), Regular, Special (intermediate) and Keotane (premium).

The development of true high-octane gasolines came to a screeching halt (along with the musclecar era) as a result of the Clean Air Act of 1970, which stipulated many federal mandates for automakers to reduce emissions of their engines. With that, General Motors President Ed Cole announced that his company’s engineers found the answer to meet these ever toughening standards – a catalytic converter, which got the job done but required the use of unleaded gasoline. As a first move toward the 1975 models that would be equipped with such devices, GM reduced compression ratios on all of its 1971 engines to permit the use of low lead, regular leaded or unleaded gasolines and other automakers soon followed. This move spelled the end of the “octane race” and as unleaded gasoline was being phased in at most U.S. service stations during 1974 in time for the 1975 and later models that would require such fuels, the higher-octane premium and super-premium leaded fuels gradually disappeared from most stations – leaving only lower-octane leaded regular and unleaded grades. By the late 1970s/early 1980s, the last of the leaded premium grades disappeared as oil companies introduced new premium unleaded fuels that were higher in octane than the unleaded regular fuels (91-83 vs. 87) – but still lacked the moxie of leaded premium fuels, leaving drivers of older cars with engines requiring high-octane gasolines with few options to keep their classic rides intact without undue engine knock, creating a cottage industry for octane boosters and, with the recent phaseout of leaded gasoline altogether, additives to replace lead as a lubricant against valve recession.
30th-November-2010, 08:50 PM
OOOooo do I remember these



“Stop and fill up with sunoco 260 action”

yes sir… it was a blue as the lakes… and smelled GOOD TOO

the difference today and 1960’s?

back then the primary was Tetra Ethel lead, to day we have ethanol and oxygenated gas.. it burns much hotter and faster…. there was unleaded fuel back in the 60’s it was known as white gas….
30th-November-2010, 11:18 PM
What do those numbers mean?
Ricky B
30th-November-2010, 11:39 PM
Union 76 premium made my ’65 El Camino run great, $1.39 gal. BITD 😀
Paul Wright
1st-December-2010, 08:18 AM
Al, Is this article your own work or someone else’s? If you didn’t write it, you need to cite the original author. Posting someone else’s work as your own is copyright infringement.
1st-December-2010, 08:34 AM
Its funny that you mention the octane ratings of yesteryear.I remember using sunoco ultra 94 in my GTO’s in the 70’s. A co-worker of mine just introduced me to some 100 octane racing fuel that he can buy near his home.Using an online calculator,I blend the 93 octane pump gas and the 100 octane o achieve approx.95 octane. This blend really gives my nova better throttle response and just runs better.

I’m thinking of tweaking it for a little higher octane this spring.
1st-December-2010, 08:48 AM
What did you guys do back in the day if you had a late 60’s 10.5:1 big block Chevelle that needed higher octane fuel in the late 70’s? Were there still stations around that sold higher octane? Sorry for the dumb question I was born in 79.
1st-December-2010, 09:25 AM
What do those numbers mean?

from this web site
Remember these?http://www.tommcmahon.net/2010/08/sunoco-blendomatic-gas-pump.html
When the 1960’s was getting under way, some changes were being made in the Sunoco camp. Instead of just 1 grade of gasoline, there were 6 different premium grades found in only 1 Blue Sunoco pump. For those of you who aren’t familiar with Sunoco during the 1960’s and early 1970’s, you might find it unusual, but clever.

When a motorist stopped at a Sunoco station, he/she called out a specific number from 200-240 or 260, and the Sunoco attendant filled the vehicle with the gasoline that went along with that particular number. The motorist had the choice of 200 (premium), 210, 220, 230, and 240 (all mid premium), and 260 (super premium). If the motorist asked for 200, the attendant moved the “Blend Selector” dial on the side of the Blue Sunoco pump to 200. From there, the attendant was ready to fill the vehicle with 200 gasoline. If the motorist asked for a higher number, it got really interesting! The Sunoco attendant moved the Blend Selector dial to the desired number. The vehicle was being filled with a combination of 200 gasoline and a specific amount of octane additive for the desired number. The higher the number, a higher amount of octane additive was used. This unique method was known as “Custom Blending.” As far as I know, Sunoco was the only oil company to do this.
however if my feeble mind is working correctly…. I recall the 190 setting = 86 octane rating and the 260 was = to 104 octane rating… by selecting the handle from point to point you got a grade some where in between the 190 and 260 mark… sunoco was known across the USA as having the highest Octane fuel in the pump of any gas available…

in doing some internet reading…. some people recall vividly the 260 at different octane ratings… as with all things… I am sure there was different levels where you were raised several people recall it ranging any where from 100 to 104 a couple of website list it @ 102 I vehemently recall it @ 104 proof!:D …. I am pretty sure PURE FIREBIRD was 102 octane.. shell had a 100 octane.. as did most stations… texaco had its superchief, gulf was ultragulf…. so hope that clears it up some what…
Fast Eddie
1st-December-2010, 09:44 AM
We had Chevron Custom in the 60’s and I bet it was above 100 octane.
1st-December-2010, 09:52 AM
up untill about 1986 regular leaded was still available… for me.. I used 5 gals of leaded regular and 15 gals of 93 unleaded.. that made 95 octane!!!! takes very little lead to keep valves happy..

plus tetra ethyl lead is very potent stuff… (kill ya quick) there was enough lead in the regular grade gas to enhance the octane level of premium unleaded fuel….

and as for big block chevelles with 10.25:1.. hahahah.. 10.5 to 1 was the stand compression ratio from about 1967 to 1970…. the 1970 315c 4bb was stock with 11.25:1 olds 400 and 455 were 10.5:1 as were the buicks, and ponchos.. try 11.25:1.. that was the common compression ration of the hot cars… and many cars were running the streets with 12.5:1

the L88 was 12.5 the max wedge 413 ‘s came in at 13:1 many of the factory race cars had compressions of 12:1 and over.. and were available for everyday driving…:D
1st-December-2010, 09:54 AM
an Arco station here that sold 99 octane until up to about 1981 if my memory is correct ,,, it was good stuff
The Big Al
1st-December-2010, 10:47 AM
In the early 70’s it was a weekly Friday trip with family, we would go tot he Hess station, fill the Buick “GS” Wagon up, and go to Shoney’s for dinner.

Dad pulled into Hess and they had stopped premium leaded gas. I thought he was going to kill someone. He was forced to go to the near by Amoco station where he used to park and sell boats. He hated the new owner. Needless to say, it was a quite dinner that evening.

The last know station in the our area of Charleston SC with the highest Octane rating was Amoco white gas. I remember as high as 102, stayed 97 for a long time. Now it’s just 91 like everyone else.
Paul Wright
1st-December-2010, 10:52 AM
What did you guys do back in the day if you had a late 60’s 10.5:1 big block Chevelle that needed higher octane fuel in the late 70’s? Were there still stations around that sold higher octane? Sorry for the dumb question I was born in 79.

I was around then (born in ’54). There were several big events that changed the fuel landscape for performance users.
In 1971 Low lead fuel was mandated by the EPA
In 1973 was the first Arab Oil Embargo. 55 mph speed limit and gas rationing. You couldn’t buy gas on Sunday.
In 1975 Lead free fuel was introduced because of Catalytic converters.
The second oil embargo was in 1979, the year you were born.
New car horsepower hit new lows by 1981.
That was when people started making the switch and buying economical Japanese cars.

In the years between 1973 and 1979 you could buy high compression big block cars dirt cheap. People were worried about the gas availability and fuel economy. Some people were burning their cars and trucks to get the insurance money because they couldn’t sell them for a good price.
A lot of the tech stories in Hot rod mags were about fuel economy and octane.
They were dark days for sure.
Paul Wright
1st-December-2010, 11:00 AM
according to Wikipedia (http://en.wikipedia.org/wiki/Sunoco), Leaded Sunoco 260 was 102 octane. That was before the R+M/2 method and lead free fuel mandates.
1st-December-2010, 11:09 AM
yeah… paul you said you hate wiki!!!! so.. but your correct many places claim 102, yet others claim 100, I have seen on the web. from 100 , 101, 102, 103, and 104…..

My own recollection from growing up in OHIO where sunoco still thrives is 104 about 1968… but I well say with out hesitation sunoco had the highest octane rating of any gas in the usa in the mid 60’s to 1970…

I dont recall when r+m/2 (ron+mon/2) came into effect… I do know it was in my life time I just dont recall the year.. as I remember it had little effect on Sun Oil Co…

after the R+M/2 ruling sunoco may have been rated at 102…. duno..
1st-December-2010, 06:32 PM
I remember when Clark Super 100 gasoline was all you could get at a Clark station. No “regular” here, just “ethyl”. It was 100 octane. Now Clark stations only carry one grade of gas…..”regular”. Their “jingle” used to be:
Clark Super 100 gasoline. Thousand say it’s best.
The largest selling independent gasoline….In the middle west.
Fill up, you’ll see. You’ll know just what we mean
With Clark Super 100 gasoline.
1st-December-2010, 09:06 PM
Wow lol I guess I should be filling up with premium hahaha. 94 was regular!! Thats insane.
1st-December-2010, 09:22 PM
Sunocco up the road from has a 93 octane “Ultra” thats the highest ive seen by me.
2nd-December-2010, 02:53 AM
worked in a phillips station until 1970. ethyl was suspose to be 104 & i believe reg was 98. gas wars had ethyl down to $.189. texas discount stations had their reg down to $.149. we used to laugh about the $.009 even back then.
2nd-December-2010, 06:41 AM
yeah… My own recollection from growing up in OHIO where sunoco still thrives is 104 about 1968…

Veno, I lived in Warren Ohio from 1954-1959 and I remember the pumps with the “dial up” numbers.

Didn’t SOHIO (Standard oil of Ohio, now BP) have something similiar?

2nd-December-2010, 09:26 AM
yeah… My own recollection from growing up in OHIO where sunoco still thrives is 104 about 1968…

Veno, I lived in Warren Ohio from 1954-1959 and I remember the pumps with the “dial up” numbers.

Didn’t SOHIO (Standard oil of Ohio, now BP) have something similiar?


Ya know.. I was trying to remember Sohio’s gas grade names… I remember mom always used Sohio… but for the life of me I cant remember the grades.. she ran nothing but the premium… and in the winter when the formula changed that had a name for it too.. but it really escapes me now….
2nd-December-2010, 06:43 PM
a friend back in the day that ran a gas station ,, he told me on a fresh delivery ,, his 93 would test out to 96 ,,, wonder if thats still the case ??

2nd-December-2010, 11:22 PM
Sunoco down the road from me has 100 on a pump :yes:

So I guess the consensus is the inline will run best on premium fuel
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What was the octane level of regular gas in the 1960s?

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1 Answer

Jon Pennington
Jon Pennington, 1970s kid with a long-time fascination about the 60s

826 Views · Most Viewed Writer in 1960s with 90+ answers
“As the subregular and middle grades of gas came to market in 1962, the average octanes of gasolines in the U.S. now stood at 93 for regular, 99 for premium and 102 for the few super-premiums still left on the market. Those numbers would increase only slightly in the next few years to around 94 octane for regular, and 100 for premium by 1967.”

Source: History of Fuel Octane! O the good old days! [Archive]