55Bfred1752

Use Of Premium Fuel

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Posted (edited)

☺️The owners manual for my recently acquired 1955 Buick Super with the 322 cu. in. engine recommends the use of premium fuel. How does the octane rating of premium fuel in 1955 compare to the 87 octane in use today/ Also, will the octane requirements of the engine be met  if 87 octane is used with the addition of a readily available octane booster additive?

Edited by 55Bfred1752 (see edit history)

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Posted (edited)

I’ve typically used at least 91 octane in my cars (which are newer than your 55). Lower octane seems to cause some pinging in my lower compression 350 in the wagon. Mostly though I use 94 octane here as it comes ethanol free which is more important to me given I don’t get to drive a lot of miles. 

 

The high compression big block in the Electra though likes 92 or above!

Edited by dmfconsult (see edit history)
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Try 87 and see if the engine knocks under load (going up a steep hill, etc). If it does, you can retard the ignition if you can, or go to 91.

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Everything I own rarely sees much over 3,000 RPM on acceleration so I just put regular in them. But I always go to the same Mobil station and never run around price shopping, so what I put in is consistent. I hardly ever take more than 10 gallons to top off, Even if gas was 10 cents cheaper I wouldn't get really excited about the ten extra dimes.

 

My '05 truck has knock sensors and I get a consistent 20 MPG. Seems fine on its diet.

 

The 12 cylinder has some pretty sophisticated controls and the book says if you put low octane gas in it you will have to buy a lot more. So that one gets fed from the high test pump, 91 maybe. All around driving average on that one is a hair over 15 MPG, not bad for a 4800 pound car, better than my Wife's Tahoe. It will do over 20 cruising.

 

I don't do any WOT driving. I think half throttle or less gets me around. Probably depends more on the nutsy right foot syndrome that anything else.

 

When I was a kid I remember reading an article about chauffeur training. It said the final test was driving with a full glass of water on the dash and not spilling any. I took that to heart way back then and have always driven like that. About 20 years ago we went out to dinner with a friend in his late model Rolls-Royce. He uses the gas and brake like binary switches. We got home and I asked her how she liked the ride in the Proper Motorcar. She said "It is really not as smooth as your Buicks." That right foot syndrome again.

 

Buy quality gas at the same place and drive with a touch of class. You'll be good at your chosen pump.

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My 54 with 264 V8 I run the lower octane without any issues. 

My 60 401 V8 I run the premium.   She'll clickity clack with anything other then premium.  

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Like all of my 55's yours will run well on 87 octane with no additives.

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Welcome!

 

Like Doug, locally premium contains no ethanol so that is what I run.  I don’t even try going lower generally.  When I’m travelling, I typically use mid-grade...if I’m south of the 49th, it’s still less expensive than our highly-taxed fuel and I’ll burn the ethanol without it having a chance to sit for any length of time and cause issues.

 

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Posted (edited)

I think it also depends on where you live and drive.  I think I fall in to the category that is discussed above, no WOT and generally take it easy on the old cars.  However, I happen to live somewhere that has lots of hills and mountains, so the cars will get a workout just hauling their heavy butts up those hills... that's where I hear the pinging.  With the higher grades, I don't get any.  Every Chevron in these parts has non-ethanol 94 octane, and yes it's more expensive, but for the miles I drive it doesn't work out to much over the year. 

Edited by dmfconsult (see edit history)
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My '58 Special has at least 140,000 miles on it and has never been opened up and still put regular in her during the summer which doesn't offer to ping but have not put my foot into it either.  

Having said that, I did put shell 91 octane in it the last recent fill up and after an 88 mile round trip noticed she seemed to be a bit more responsive on the throttle.

My imagination? Maybe but it was one of those humid cool days and I always felt that made a difference too. 

 

Was told by a well known Cadillac collector around here that Shell high test does not have the ethanol in it and will not evaporate as bad when storing cars over the winters.

His collection has quite a collection of V16's which he says are all kept up and driven as regularly as he can so figure his experience is trust worthy.

IMG_3161.thumb.JPG.32c340a9fae42cc541c831181a498fa4.JPG

 

I must say he has a '58 Special convertible also so again, his experience counts for something.

IMG_3213_Easy-Resize_com.thumb.jpg.388f8d17d7cdd79df898e5afb97f32bb.jpg

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In "the old Research Octane" ratings, in 1957, "Ethyl" was 97 Research Octane rating, typically.  That would mean that some "premiums" might have been 95 Research Octane as others maxed-out at 97.  By about 1960, "Premium" was closer to 100 Research Octane.

 

What's on the pumps is "Pump Octane", which is the average of Research Octane and Motor Octane.  The Motor method generates lower octane numbers, with Research being higher numbers . . . for the same fuel being tested.  Typically, you can add "4" to the Pump Octane to approximate Research Octane.

 

Ethyl was 97-100 Research Octane.    Regular was usually 94-95 Research Octane    Sub-Regular was more like 91 Research Octane.  All before "Low-Lead" came out.  Taking the lead out usually resulted in Research Octane of about "2" less than fully-leaded fuel.  

 

In 1974, Premium was 94-95.5 Pump Octane.    Regular was 91-92 Pump Octane (later termed "Mid-Grade" by some).    Sub-Regular was 89 Pump Octane.  Decrease these low-lead numbers by "2" and you tend to get what we have now.  87/89/91-93, "Regular", "Mid-Grade", "Premium", respectively.

 

Higher elevations means less effective cylinder pressure (thinner atmosphere), so less octane is needed.

 

In general, just like in prior times, it's a "Try and see" situation.

 

Many current octane boosters usually have some sort of alcohol/ethanol in them to raise the fuel's octane a few numbers.  Best to fine the fuel that works best and use it!  If clattering persists, then something like Berryman's B-12 in the gas tank prior to a "two-tank" length trip might work best in getting the combustion chambers cleaned out of carbon deposits.  NOTHING works instantly, as many imply.

 

Just some thoughts,

NTX5467

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Posted (edited)
49 minutes ago, dei said:

My '58 Special has at least 140,000 miles on it and has never been opened up and still put regular in her during the summer which doesn't offer to ping but have not put my foot into it either.  

Having said that, I did put shell 91 octane in it the last recent fill up and after an 88 mile round trip noticed she seemed to be a bit more responsive on the throttle.

My imagination? Maybe but it was one of those humid cool days and I always felt that made a difference too. 

 

Was told by a well known Cadillac collector around here that Shell high test does not have the ethanol in it and will not evaporate as bad when storing cars over the winters.

His collection has quite a collection of V16's which he says are all kept up and driven as regularly as he can so figure his experience is trust worthy.

 

 

 

You can get Shell 91 non-ethanol around here to Doug, but it is the same price as the Chevron 94 non-ethanol, so I go with the Chevron!

 

I will also add a few ounces of Marvel Mystery Oil to the gas in the 67 to provide some top end lubrication from time to time.  This may or may not work, but I figure it may replace what lubrication leaded fuel provided back in the day.  If it doesn't do anything, I really haven't lost anything!

Edited by dmfconsult (see edit history)
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2 minutes ago, dmfconsult said:

You can get Shell 91 non-ethanol around here to Doug, but it is the same price as the Chevron 94 non-ethanol, so I go with the Chevron!

 

We don't have Chevron Gas Stations here in Ontario Canada and I think 94 non-ethanol / unleaded was last seen at the Sunoco Stations quite a few years ago.

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2 minutes ago, dei said:

 

We don't have Chevron Gas Stations here in Ontario Canada and I think 94 non-ethanol / unleaded was last seen at the Sunoco Stations quite a few years ago.

 

That is a pity and I did notice that when we were in Ontario over the summer. 

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It’s been touched on, but I’ll hit it again. Stay away from ethanol. There are 2 major issues with it:

 

1.  It will degrade your soft parts.  You’ll buy more fuel pumps if you feed it moonshine. 

 

2.  Ethanol is hygroscopic. It will absorb water out of the air, which will separate out of the gasoline and settle at the low points. Older cars weren’t as corrosion resistant, and the more the car sits, the more this becomes an issue. As I’m betting your ‘55 is not your daily driver, it’s more likely to be mixing up a little scotch & water when you’re not around. 

 

 

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 It would be nice to stay away from ethanol fuel. However I don't think it's worth driving an hour and a half out of my way every time I want to purchase gas.

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Well I've been driving my car daily and I'm still using the same fuel pump. I've never had an issue other than a once in a while fuel bowl boil during a heat soak. I can understand only driving the car during the summer, but then you would just need to drain the tank during the off season and purge the lines to the carb, then during the on season drive up and get 5 gallons and be on your way in your classic. As long as you continue to drive, it shouldn't be much of an issue. There's a lot of scare hype for ethanol fuel and I have had almost zero of the issues that always come up.My biggest complaint is that the fuel is bad for the carbs in the sense that the way the fuel burns and behaves is different from the 50s, obviously. Regardless, I keep motoring on with 10%. No rust through of my original lines yet, no rust scale in the filter and my rubber hoses aren't cracking and deteriorating. 

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9 hours ago, Beemon said:

Well I've been driving my car daily and I'm still using the same fuel pump. I've never had an issue other than a once in a while fuel bowl boil during a heat soak. I can understand only driving the car during the summer, but then you would just need to drain the tank during the off season and purge the lines to the carb, then during the on season drive up and get 5 gallons and be on your way in your classic. As long as you continue to drive, it shouldn't be much of an issue. There's a lot of scare hype for ethanol fuel and I have had almost zero of the issues that always come up.My biggest complaint is that the fuel is bad for the carbs in the sense that the way the fuel burns and behaves is different from the 50s, obviously. Regardless, I keep motoring on with 10%. No rust through of my original lines yet, no rust scale in the filter and my rubber hoses aren't cracking and deteriorating. 

 

I have a '51 Nash Canadian Statesman from Dad that about 10 years ago when idling suddenly started leaving oil spots underneath her. There were no visible leaks but after wiping off the side of the block, noticed the dipstick would spew something out from under the head of the stick. Smelled it and it had an odour of gas to it and the oil was very thin!

Put a new fuel pump on and looked at the old one. Age? Fuel? Maybe both...

Sadly, we hear the lifters from that little 6 cylinder more now since Dad ran it like that for a few jaunts...

552026095_1951Nash-WillisteadClassicCarShow1990.thumb.jpg.6f052afba9c9517f9eea0d6ae5b19538.jpg

 

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33 minutes ago, dei said:

 

I have a '51 Nash Canadian Statesman from Dad that about 10 years ago when idling suddenly started leaving oil spots underneath her. There were no visible leaks but after wiping off the side of the block, noticed the dipstick would spew something out from under the head of the stick. Smelled it and it had an odour of gas to it and the oil was very thin!

Put a new fuel pump on and looked at the old one. Age? Fuel? Maybe both...

Sadly, we hear the lifters from that little 6 cylinder more now since Dad ran it like that for a few jaunts...

552026095_1951Nash-WillisteadClassicCarShow1990.thumb.jpg.6f052afba9c9517f9eea0d6ae5b19538.jpg

 

 

Sounds like the diaphram cracked and leaked gas into the crankcase. Pretty common if your using an old fuel pump or NOS. Modern rebuild kits usually have ethanol resist parts so it should fix the problem.

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Ya.......what Willis, Willie, and the others said.

In my case, my '39 runs fine on regular,  but the rumors are that premium has LESS ethanol in it than regular.  so I don't drive mine much so I fill with premium trying to avoid ethanol.......locally gas without ethanol has started to show up but the price per gallon is the same as premium.     If you haven't noticed, MID-grade is a mixture of regular and premium.   the pumps do the mixing and if you do the math, 

you can do that manually by alternating between regular and premium at fill-ups.

 

At the Denver national meet,  I attended the tech sessions for early Buicks.   On of the interesting subjects was the use of additives.   The "experts" and attendees got on the subject of Marvel Mystery Oil.  

The feeling in the room was it is a wonderful product.  It can be added both to the oil and gas with benefits (go to the web site)   attendees said it works like a gas stabilizer and cost less per treatment, 

most said they used it in the gas of anything with a gas engine what was not used regularly .

The general feeling was it took the place of the additives for ethanol gas and long storage.     I have started using it but it is too early to give an opinion.

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Luckily where I live there is a ready supply of Non- Ethanol, which is what I put in all my cars.  However, if I am on a trip I have no issue with ethanol gas.  I do not think it is a problem if it is used up in a relatively short time span,  like one to two weeks.  Unlike Barney though, I was under the impression that the lowest octane rated ethanol product has the least amount of ethanol.   But I am not to be quoted as the source on that.  Last time I had to use ethanol on a trip with the 72 I did use the lowest octane rated product and did not notice any difference in performance, on the low compression 455,  cruising down the highways of Pennsylvania.

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1 hour ago, dei said:

 

I have a '51 Nash Canadian Statesman from Dad that about 10 years ago when idling suddenly started leaving oil spots underneath her. There were no visible leaks but after wiping off the side of the block, noticed the dipstick would spew something out from under the head of the stick. Smelled it and it had an odour of gas to it and the oil was very thin!

Put a new fuel pump on and looked at the old one. Age? Fuel? Maybe both...

Sadly, we hear the lifters from that little 6 cylinder more now since Dad ran it like that for a few jaunts...

552026095_1951Nash-WillisteadClassicCarShow1990.thumb.jpg.6f052afba9c9517f9eea0d6ae5b19538.jpg

 

Oil coming from the dip stick tube is usually an indicator of excess pressure in the crank case.  This car predates PCV valves so I imagine that it has a blow-by tube.  I'd check that tube to ensure that it's not blocked.

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3 hours ago, Barney Eaton said:

the rumors are that premium has LESS ethanol in it than regular. 

Probably has more since ethanol is an octane booster.

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Posted (edited)

 You get 87 octane fuel by mixing 10% 113 octane (pure) Ethanol with 85 octane gasoline.  The octane rating of E85 is 108.  Ethanol when mixed with gasoline is actually an octane booster. 

 

Who keeps coming up with all of these urban myths about Ethanol? 

 

True, you'll have some evaporation if you don't run your engine often, and you'll have some problems with gaskets exposed to Ethanol, but isn't the clean air worth it?  When I drove to work in Kansas City in the early 1970's, I was always greeted with that brown smog hanging over the city.  I really don't miss that. 

 

Take some time and get some Ethanol proof gaskets for your carburetor, put premium gas in the tank, and live life a little less stress free.  (One less thing to mull over and gripe about.)

Edited by RivNut (see edit history)
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All the pumps here say "contains up to 10% ethanol". Doesn't really matter what you put in, it could be 2% or it could be 10%. There aren't any ethanol free pumps near me that I know of. But i gotta say, my plugs are never fouled, even after the carb has ran rich. 

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