What octane level was the standard for premium in 1970?
May 18th, 2014, 10:18 AM
#6
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"Sunoco is perhaps best known to consumers for its "custom blending" pumps, an innovation that, beginning in 1956, allowed customers of Sunoco service stations to choose from several octane grades through a single pump. Sunoco stations offered as many as eight grades of "Custom Blended" gasolines from its "Dial A Grade" pumps ranging from subregular Sunoco 190 to Sunoco 260, the latter a super-premium grade of 102 octane that was advertised as the "highest octane pump gas" and very popular with V8-powered Muscle Cars of the 1960s."
Taken from the web. Sunoco 260 was the stuff!
Taken from the web. Sunoco 260 was the stuff!
May 18th, 2014, 11:08 AM
#8
Just an Olds Guy
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Gas octane was rated differently back in 1970. If you use Premium unleaded today it will be about the same octane value as premium leaded back in the day. This topic has been discussed to death on this site, same as what type of oil to use.
Either Google search or the site search will pull up the topics for review you need.
Either Google search or the site search will pull up the topics for review you need.
May 18th, 2014, 01:43 PM
#11
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Allan R - Sorry, I did not realize this topic had been "discussed to death"
Not an expert, but there are many that would disagree with your comment that todays unleaded premium is the equivalent in octane vs the 60's/70's. Some don't believe that todays 93 unleaded premium actually exceeds 89 octane. Many top restoration shops go to the trouble of running newly rebuilt engines with fuel purchased at airports (lot of trouble if the unleaded premium is equal to 99 rated octanes purchased at race tracks/airports). Anyway, my original question was simply what was the octane rating of premium gas around the year 1970
May 18th, 2014, 01:46 PM
#12
morgan
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Yes the sunoco 260 was tops...i remember some stations had just a 260 pump and we used to always complain if we bought it on the mult-pump because we used to think the gas stayed in the hose and the previous person didnt get the high test so the lower octane would be still in the hose.
May 18th, 2014, 02:43 PM
#13
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Not an expert, but there are many that would disagree with your comment that todays unleaded premium is the equivalent in octane vs the 60's/70's. Some don't believe that todays 93 unleaded premium actually exceeds 89 octane. .......Anyway, my original question was simply what was the octane rating of premium gas around the year 1970
Remember when you claim 103 octane in 1970 it was measured by Research Octane Number (RON), not Motor Octane Number (MON), which gasoline is now rated by. A RON rating of 103 would be between 8 and 10 points higher (than a MON rating) in 1970 for exactly the same product. So I stand by my original comments. Only thing significantly different about 1970 pump gas compared to now was the Tetra ethyl additive.
BTW some people don't believe the 94 octane exceeds 89 because of the AKI Anti knock index which is known in the US and Canada, but not generally in the rest of the world. The AKI makes the fuel appear to be 4-5 points lower in octane, but it isn't. It's just not being compared the same. You have to compare apples to apples, not watermelons.
May 18th, 2014, 03:18 PM
#15
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93 or 94 octane is Premium fuel measured in MON. It could be the equivalent of about 104-105 on the old RON rating, but I'm not sure I understand your question/comment. Why is it important to determine the RON rating of fuel you're buying today when it's the only stuff you can buy anyway, rated by MON?
Here's something I posted before on the topic so - cut/paste. You can read and decide what you want. It's truthful, but if you want to call BS that's up to you.
I got the following quote from a chevy forum. (Yeah I know, but they also run the same gas issues as we do) The writeup starts out as a tribute to the Camaro, but goes on to talk about the burdens GM faced with performance when congress introduced the Clean Air Act in 1970, and then legislated lead free gasoline in 72. I also found out that AMOCO actually produced lead free gas from earlier than 1920!!
Here's something I posted before on the topic so - cut/paste. You can read and decide what you want. It's truthful, but if you want to call BS that's up to you.
Try looking at it this way:
Remember when 100 octane was common? Sunoco260 gasoline was listed at the pump at 102 octane. Those octane ratings sound very high compared to today's octane ratings, but they were not as much higher. Why? Because there are 2 ways to rate octane. One is called the "research" octane number RON and the other is called the "motor" octane number. MON
The research octane number is ALWAYS a higher number than the motor octane number, so when oil companies used to advertise their Hi-Test gasoline, they used the more impressive research octane number. This gave the average consumer the impression that the gas had more power than it actually did. Ah yes, the days of "fill'er up with hi test'. And at only 2cents a gallon difference? Why would you settle for regular, right?
But "motor" octane is a number about 10 points lower than the Research number, because that was measured when the engine was under load. The oil companies didn't advertise that lower number.
In 1972, government legislated oil companies to post an average of the 2 different octane ratings, which lowers the octane rating number for the same fuel that had higher numbers before. That's no doubt why GM included - even the 72 owners manual - to use the gasoline Research octane number in their fuel recommendations. The books were already printed or in print when the legislation was passed. And it takes a while to filter down to production.....
So when you look on a gas pump, you'll see a sticker for the octane rating that says "R+M/2", which stands for Research octane plus Motor octane divided by 2, which is the average of both rating numbers.
Using that information, if you look at the old 100 Research octane, it also had a Motor octane rating of about 90. Today that is posted as the 'average' of about 95
That's still a little higher than the 93 or 94 octane of today's Premium, but not as big a difference as most people think. The conversion from 91 octane in the old days to 87 now is the result of 91 research octane added to 84 motor octane averaged to 87. So you're still getting about the same octane rating, but with with ethanol additives to give the octane rating instead of tetraethyl lead.
Remember when 100 octane was common? Sunoco260 gasoline was listed at the pump at 102 octane. Those octane ratings sound very high compared to today's octane ratings, but they were not as much higher. Why? Because there are 2 ways to rate octane. One is called the "research" octane number RON and the other is called the "motor" octane number. MON
The research octane number is ALWAYS a higher number than the motor octane number, so when oil companies used to advertise their Hi-Test gasoline, they used the more impressive research octane number. This gave the average consumer the impression that the gas had more power than it actually did. Ah yes, the days of "fill'er up with hi test'. And at only 2cents a gallon difference? Why would you settle for regular, right?
But "motor" octane is a number about 10 points lower than the Research number, because that was measured when the engine was under load. The oil companies didn't advertise that lower number.
In 1972, government legislated oil companies to post an average of the 2 different octane ratings, which lowers the octane rating number for the same fuel that had higher numbers before. That's no doubt why GM included - even the 72 owners manual - to use the gasoline Research octane number in their fuel recommendations. The books were already printed or in print when the legislation was passed. And it takes a while to filter down to production.....
So when you look on a gas pump, you'll see a sticker for the octane rating that says "R+M/2", which stands for Research octane plus Motor octane divided by 2, which is the average of both rating numbers.
Using that information, if you look at the old 100 Research octane, it also had a Motor octane rating of about 90. Today that is posted as the 'average' of about 95
That's still a little higher than the 93 or 94 octane of today's Premium, but not as big a difference as most people think. The conversion from 91 octane in the old days to 87 now is the result of 91 research octane added to 84 motor octane averaged to 87. So you're still getting about the same octane rating, but with with ethanol additives to give the octane rating instead of tetraethyl lead.
Originally Posted by Mark Potter
That is correct about the change in gasoline octane measurements from "Research" in the 1960s to today's "Pump" octane is somewhat similar to the changes in engine horsepower measurements from the "gross" figures of 1971 and earlier on a dynometer without mufflers, accessories and emission equipment, to the "net" ratings of 1972 and later that were based on an engine as "installed" in a vehicle with exhaust system, accessories and emission controls installed.
Today's 87 "Pump" octane unleaded regular is the same fuel as the 91 "Research" octane fuel that was recommended in the 1971 Camaro owner's manual. Similar spreads of 4-5 octane differences in fuels between pump and research exist for mid-grade unleaded - 89 Pump octane or 93 Research octane (just slightly below the 94 research octane for regular-grade fuel in 1971) and 93 Pump octane unleaded premium would be 97-98 research octane, or just slightly below the 99-100 research octane of leaded premium in that era.
Another fact to consider. While almost all oil companies went to lead to increase gasoline octane in the 1920s and 1930s, American Oil Company continued to market its premium-grade gasoline - Amoco - as a lead-free fuel utilizing aromatics as an octane booster (American's regular gas however was a leaded fuel as it was not as economical to sell the high-volume low-priced gasoline as a lead-free due to high production costs). Amoco was sold in several eastern and southern states since the 1910s. The lead free gasoline was marketed as simply Amoco or Amoco-Gas until 1961 when it was renamed American Super-Premium, and had reached a Research octane of 100 - similar to competitor's leaded premium fuels - but sold about 1 to 2 cents higher per gallon.
I would like to see or hear former muscle car owners back in the day who predominately used Amoco's lead-free premium when those cars were new - and how well their vehicles held up in the face of reports that pre-1971 engines could suffer valve recession and other damage from predominant use of such fuel that continue to this day. I have heard of reports from owners of 50s and 60s cars with high-compression engines that used Amoco Super-Premium almost exclusively including Buicks, Cadillacs and Chryslers, stating that spark plugs were cleaner and lasted longer, and exhaust systems lasted much longer due to absence of corrosion caused by use of leaded gasoline.
That is correct about the change in gasoline octane measurements from "Research" in the 1960s to today's "Pump" octane is somewhat similar to the changes in engine horsepower measurements from the "gross" figures of 1971 and earlier on a dynometer without mufflers, accessories and emission equipment, to the "net" ratings of 1972 and later that were based on an engine as "installed" in a vehicle with exhaust system, accessories and emission controls installed.
Today's 87 "Pump" octane unleaded regular is the same fuel as the 91 "Research" octane fuel that was recommended in the 1971 Camaro owner's manual. Similar spreads of 4-5 octane differences in fuels between pump and research exist for mid-grade unleaded - 89 Pump octane or 93 Research octane (just slightly below the 94 research octane for regular-grade fuel in 1971) and 93 Pump octane unleaded premium would be 97-98 research octane, or just slightly below the 99-100 research octane of leaded premium in that era.
Another fact to consider. While almost all oil companies went to lead to increase gasoline octane in the 1920s and 1930s, American Oil Company continued to market its premium-grade gasoline - Amoco - as a lead-free fuel utilizing aromatics as an octane booster (American's regular gas however was a leaded fuel as it was not as economical to sell the high-volume low-priced gasoline as a lead-free due to high production costs). Amoco was sold in several eastern and southern states since the 1910s. The lead free gasoline was marketed as simply Amoco or Amoco-Gas until 1961 when it was renamed American Super-Premium, and had reached a Research octane of 100 - similar to competitor's leaded premium fuels - but sold about 1 to 2 cents higher per gallon.
I would like to see or hear former muscle car owners back in the day who predominately used Amoco's lead-free premium when those cars were new - and how well their vehicles held up in the face of reports that pre-1971 engines could suffer valve recession and other damage from predominant use of such fuel that continue to this day. I have heard of reports from owners of 50s and 60s cars with high-compression engines that used Amoco Super-Premium almost exclusively including Buicks, Cadillacs and Chryslers, stating that spark plugs were cleaner and lasted longer, and exhaust systems lasted much longer due to absence of corrosion caused by use of leaded gasoline.
May 18th, 2014, 03:33 PM
#16
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If I recall correctly, we ran Crown premium or Sunoco 260 that had a label on the pump listing 104. This was for our high comp. stock car engines, late 60s, early 70s.
My dad ran American or Amoco exclusively. He worked for American oil, later Amoco.
He certainly believed plugs and exhaust lasted longer and had no valve problems in his stock V-8s in the 60s and 70s.
My dad ran American or Amoco exclusively. He worked for American oil, later Amoco.
He certainly believed plugs and exhaust lasted longer and had no valve problems in his stock V-8s in the 60s and 70s.
May 18th, 2014, 04:15 PM
#17
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Premium fuel in 1970 was 100 RON octane, about 102-103 for Super.
That's about 96 or 96 according to the current US AKI scale for premium, about 98 for Super.
The Europeans still use the RON scale, so their current numbers are teh same as out old numbers, and their premium is about 98, which is still about 2 points too low for a 1970 high compression motor.
- Eric
That's about 96 or 96 according to the current US AKI scale for premium, about 98 for Super.
The Europeans still use the RON scale, so their current numbers are teh same as out old numbers, and their premium is about 98, which is still about 2 points too low for a 1970 high compression motor.
- Eric
May 18th, 2014, 07:57 PM
#19
morgan
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I understand that but i didnt realize or pay much attention the fact that the current octane rating are comparable to the 70's and the quantity of additive is probably more than ive been using
May 18th, 2014, 09:35 PM
#20
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I haven't paid that close of attention to it, but I would swear that the pumps are still labeled as:
R+N
----
2
for their octane ratings. Guess I'll have to look again just to satisfy my own curiosity. Whatever the octane rating, most of it is still crap if you are stuck with ethanol spiked gas compared to "straight" gas from an energy content standpoint. Didn't have to worry about that in the old days...
R+N
----
2
for their octane ratings. Guess I'll have to look again just to satisfy my own curiosity. Whatever the octane rating, most of it is still crap if you are stuck with ethanol spiked gas compared to "straight" gas from an energy content standpoint. Didn't have to worry about that in the old days...
May 19th, 2014, 02:58 AM
#21
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Plus, your wallet will get a lot thinner.
- Eric
May 19th, 2014, 03:01 AM
#22
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May 19th, 2014, 12:04 PM
#23
Just an Olds Guy
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To get a full 10 point gain in octane from octane Supreme, you'd need to add around 5.5 oz per gallon to see a 10 octane point boost. Lessee now - 5.5 oz / gallon X 20 gallons? You'd need about 110 oz per tank to get the extra octane gas. Cost of this venture? A case of 12 Octane supreme - 188.00 + shipping (steal of a deal). Amount used each full fill would be 3.5 quarts (almost an oil change huh?) of Octane supreme @ 15.60/quart = $54.60 just for octane booster. Add that to the cost of premium fuel (conservative est: 3.50/gal) and the total fill bill would be 70 + 54.60, or a whopping 124.60!! Is it really worth it?
The non TEL octane boosters are a waste of $ IMO - it doesn't add what most peeps think. It adds a small number of (partial) 'points' to the octane. Say you have 94 octane and buy OTC Octane booster that says it'll raise octane by 7 points. That translates to 94.7 octane, NOT 101. Lead additives DO add octane value, but it has to be on at least 3/4 tank to be really effective. For the $ spent on Octane boosters, it's more practical to just buy the highest rated premium octane you can. Just make sure it's the right fuel for your engine. If you're running a low compression engine, you're wasting your money.
I haven't paid that close of attention to it, but I would swear that the pumps are still labeled as:
R+N
----
2
for their octane ratings. Guess I'll have to look again just to satisfy my own curiosity. Whatever the octane rating, most of it is still crap if you are stuck with ethanol spiked gas compared to "straight" gas from an energy content standpoint. Didn't have to worry about that in the old days...
R+N
----
2
for their octane ratings. Guess I'll have to look again just to satisfy my own curiosity. Whatever the octane rating, most of it is still crap if you are stuck with ethanol spiked gas compared to "straight" gas from an energy content standpoint. Didn't have to worry about that in the old days...
May 19th, 2014, 01:08 PM
#24
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I haven't seen 94 octane in ten or twenty years.
The max I've seen in NY, NJ, CT, Mass, and NH has been 93, and the max in Maine 91.
If you've seen 95, please tell me where, because I've never seen that since they came out with standardized pump labels around 1980.
- Eric
May 19th, 2014, 01:31 PM
#25
Just an Olds Guy
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Yer kiddin right?
Shell V-Power premium is 91, Esso premium is 93 and Petrocan ULTRA is 94 at the pump - at least here in Canada it is. So adding OS to the lower R+M/2 would net a lower number than I thought in the first place. That would make existing stocks of premium gasoline almost par with the olde octane ratings for the early 70's. If RON was 100 in 1970, what was MON? Blend these 2 numbers and I bet you get the same numeric value as what's at the pump now.
I was also confused by your post that included
What exactly were you trying to say??
Shell V-Power premium is 91, Esso premium is 93 and Petrocan ULTRA is 94 at the pump - at least here in Canada it is. So adding OS to the lower R+M/2 would net a lower number than I thought in the first place. That would make existing stocks of premium gasoline almost par with the olde octane ratings for the early 70's. If RON was 100 in 1970, what was MON? Blend these 2 numbers and I bet you get the same numeric value as what's at the pump now.
I was also confused by your post that included
That's about 96 or 96 according to the current US AKI scale for premium, about 98 for Super
May 19th, 2014, 01:45 PM
#26
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Well, in Canada, maybe, but not here in the northeastern US, that's for sure.
As I say, I haven't seen 94 in many years, and then it was only at Sunoco, and maybe Chevron.
I was trying to say that if you were looking for Premium RON gas, the number on a modern US pump would read 95 or 96, and if you were looking for Super, it would read 98, so if the pump at your station has a lower number, you'll need to use some octane boost or retard the timing.
- Eric
As I say, I haven't seen 94 in many years, and then it was only at Sunoco, and maybe Chevron.
- Eric
May 19th, 2014, 01:53 PM
#27
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Ahh, so the 96/96 was a typo. No sweat, just confused me.
You're always welcome to come up and buy some of our 94 oct gas. You'll be in for a shock though when you look at the pump price. It's sold by the litre (so 3.78 to your gallon) with a huge wallop of taxes thrown in to start the peasant revolt! Your price per gallon would be approx $5.17 So a 20 gallon fill would be an easy franklin. Gotta love BMW and Imports that 'require' premium - so does big oil apparently. 9/10
You're always welcome to come up and buy some of our 94 oct gas. You'll be in for a shock though when you look at the pump price. It's sold by the litre (so 3.78 to your gallon) with a huge wallop of taxes thrown in to start the peasant revolt! Your price per gallon would be approx $5.17 So a 20 gallon fill would be an easy franklin. Gotta love BMW and Imports that 'require' premium - so does big oil apparently. 9/10
May 19th, 2014, 02:23 PM
#29
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I've been doing some research.
Pure-gas.org is your friend. In my area, Evansville, I can get 91 ethanol free out of CountryMark, and there's some 93 ethanol free nearby as well. A few stations sell Sunoco 110 Leaded rocket fuel, but I don't need that for anything yet.
Pure-gas.org is your friend. In my area, Evansville, I can get 91 ethanol free out of CountryMark, and there's some 93 ethanol free nearby as well. A few stations sell Sunoco 110 Leaded rocket fuel, but I don't need that for anything yet.
May 19th, 2014, 02:56 PM
#31
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May 19th, 2014, 04:13 PM
#34
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I think the pricing in the US is less heavily weighted towards taxes? The $ values I was using were a low rough estimate of averaging. The reality is 5.17/US gallon would be a bargain here. Reality is 5.48 (Halifax) to 6.20 (Vancouver) All those prices adjusted for US gallon. I see TX averages from 3.24 to 3.54/gal of premium. Even CA premium is only about 4.05/gal. Even Maine (where the other other Eric lives) is only around 3.95/gal.
Anyway, this is getting off topic.
Anyway, this is getting off topic.
May 19th, 2014, 04:54 PM
#36
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The blended numbers (R+M)/2 already are a better indicator of gasolines performance than going by the old RON number alone. Remember you're adding a straight whole number octane supplement/gallon - see the OS chart. The 93 is already the equivalent (not exact, but equivalent) of an older rating system.
A 103 RON is the high end value of an old marketing system. Now add the MON component of 103 (which will be around 83-84) and you get 186. Divide that by 2 = 93. So when you fill your car with 93 (min) octane premium fuel, you're already at the old RON system you're stuck on here.
Even if you fill your car with 91 premium and add a full quart of OS to the tank you would still have more octane rating than the OLD 103 RON rating. Just it will cost you an extra 22 bucks or so per tank of fuel for the OS. Your call on how you want to spend your money.
May 19th, 2014, 07:17 PM
#37
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If you buy 93AKI octane at the local gas station, you need to add enough octane booster to get it to 98AKI, which will be the rough equivalent of 103RON.
This is because the difference between AKI and RON in the range we are discussing is somewhere between 4-6 points (actual MON and RON measurements on the actual test engines will not always be the same distance apart - they will depend on the exact additive packages of each sample of gasoline provided, so there is no absolute mathematical relation).
So, if you want your 93AKI (~98RON) gasoline to be like 103RON (~98AKI), you need to get it about 5 points higher.
Following the chart
, we can see that we need to add about 1.8oz of Octane Supreme to get 93AKI (~98RON) to ~98AKI (~103RON).Note that the amount of additive needed increases faster than the increase in octane, ie: 0.6oz/gal will get you 2 points, but twice that amount, 1.2oz/gal, will only get you 3.5 points (not 4), and 2.4oz/gal will only get you 6.5 points (not 8).
This means that it is cheapest to use the highest octane you can get from the pump and use as little additive as possible.
- Eric
