Octane

[C&C]

Not all premium gasolines are inherently better than their regular grade. There was a thread that ran its course a while back that discussed Top Tier gasolines (I think it ran on this forum), which stated that some gasoline companies were meeting quality standards in all grades of their gasolines. More can be learned by visiting: https://www.toptiergas.com They also list the gasoline companies that meet this standard.

 

[jestal]

Absolutely true that it is no guarantee that you will get the best additive package all the time but buying premium from the majors stacks the deck in your favor. There have been several situations over the past years that I was involved with where problems cropped up with particular brands of fuel in certain areas that also tends to support the idea that the majors put a better additive package in premium.

In any area all the gasoline likely comes from the same terminal anyway.....so the gasoline itself is the same. The only difference is the additive package in the fuel and the improved quality assurance from the majors that you are not buying a load of alcohol in the fuel.

There are many factors that affect the power output of an engine on a dyno. Even the volitility of the fuel can affect atomization and fuel distribution and HP....and that has nothing to do with octane rating. I've seen numerous dyno tests on some pretty sophisticated dynos trying to "prove" that regular makes more power than premium....only to prove that it doesn't matter.

Weed eaters work great at about 40:1 on Citgo Sea and Snow two stroke oil premixed. The Citgo Sea and Snow two stroke oil is one of the better products on the market and is actually one of the less expensive. We go thru gallons of the stuff in the winter in sleds and it works excellently. No reason to go leaner on oil as many studies prove that the more oil the better for HP basically. Just remember that if the carb is running premix then changing the premix ratio will change the A/F ratio the engine is running at (oil replaces gasoline in the jet so more oil equals less fuel and a leaner mixture) so you have to set the carb up on the premix ratio and stick with it. Believe it or not.....I have done some "research" on this with mod'ed weedeater engines....LOL. You should hear my leaf blower run. It is the envy of the neighborhood.

 

[sparky3008]

Absolutely true that it is no guarantee that you will get the best additive package all the time but buying premium from the majors stacks the deck in your favor. There have been several situations over the past years that I was involved with where problems cropped up with particular brands of fuel in certain areas that also tends to support the idea that the majors put a better additive package in premium.
In any area all the gasoline likely comes from the same terminal anyway.....so the gasoline itself is the same. The only difference is the additive package in the fuel and the improved quality assurance from the majors that you are not buying a load of alcohol in the fuel.

There are many factors that affect the power output of an engine on a dyno. Even the volitility of the fuel can affect atomization and fuel distribution and HP....and that has nothing to do with octane rating. I've seen numerous dyno tests on some pretty sophisticated dynos trying to "prove" that regular makes more power than premium....only to prove that it doesn't matter.

Weed eaters work great at about 40:1 on Citgo Sea and Snow two stroke oil premixed. The Citgo Sea and Snow two stroke oil is one of the better products on the market and is actually one of the less expensive. We go thru gallons of the stuff in the winter in sleds and it works excellently. No reason to go leaner on oil as many studies prove that the more oil the better for HP basically. Just remember that if the carb is running premix then changing the premix ratio will change the A/F ratio the engine is running at (oil replaces gasoline in the jet so more oil equals less fuel and a leaner mixture) so you have to set the carb up on the premix ratio and stick with it. Believe it or not.....I have done some "research" on this with mod'ed weedeater engines....LOL. You should hear my leaf blower run. It is the envy of the neighborhood.

After I wrote 50:1 I started thinking it might be 32:1 that the little bottle recommend. I ain't mixed it in a while :lol:

 

[evil_henchman]

Absolutely true that it is no guarantee that you will get the best additive package all the time but buying premium from the majors stacks the deck in your favor. There have been several situations over the past years that I was involved with where problems cropped up with particular brands of fuel in certain areas that also tends to support the idea that the majors put a better additive package in premium.
In any area all the gasoline likely comes from the same terminal anyway.....so the gasoline itself is the same. The only difference is the additive package in the fuel and the improved quality assurance from the majors that you are not buying a load of alcohol in the fuel.

There are many factors that affect the power output of an engine on a dyno. Even the volitility of the fuel can affect atomization and fuel distribution and HP....and that has nothing to do with octane rating. I've seen numerous dyno tests on some pretty sophisticated dynos trying to "prove" that regular makes more power than premium....only to prove that it doesn't matter.

Weed eaters work great at about 40:1 on Citgo Sea and Snow two stroke oil premixed. The Citgo Sea and Snow two stroke oil is one of the better products on the market and is actually one of the less expensive. We go thru gallons of the stuff in the winter in sleds and it works excellently. No reason to go leaner on oil as many studies prove that the more oil the better for HP basically. Just remember that if the carb is running premix then changing the premix ratio will change the A/F ratio the engine is running at (oil replaces gasoline in the jet so more oil equals less fuel and a leaner mixture) so you have to set the carb up on the premix ratio and stick with it. Believe it or not.....I have done some "research" on this with mod'ed weedeater engines....LOL. You should hear my leaf blower run. It is the envy of the neighborhood.

I couldn't agree more that it pays to by gas from the majors. In another life I worked at a refinery and I screwed up my share of gas and oil and believe me, there's a thriving market for low priced off spec product. The majors don't sell it at their own stations but they damn sure sell it. We had a guy who specialized in selling it and the Habib's type gas & liquor stores line up to buy it. Even now in my current incarnation I just sold 25,000 gallons of 10 year old #2 diesel fuel to a major distributor (not a refiner) who just blended it in with their stock. Buyer beware.

 

[sparky3008]

Absolutely true that it is no guarantee that you will get the best additive package all the time but buying premium from the majors stacks the deck in your favor. There have been several situations over the past years that I was involved with where problems cropped up with particular brands of fuel in certain areas that also tends to support the idea that the majors put a better additive package in premium.

In any area all the gasoline likely comes from the same terminal anyway.....so the gasoline itself is the same. The only difference is the additive package in the fuel and the improved quality assurance from the majors that you are not buying a load of alcohol in the fuel.

There are many factors that affect the power output of an engine on a dyno. Even the volitility of the fuel can affect atomization and fuel distribution and HP....and that has nothing to do with octane rating. I've seen numerous dyno tests on some pretty sophisticated dynos trying to "prove" that regular makes more power than premium....only to prove that it doesn't matter.

Weed eaters work great at about 40:1 on Citgo Sea and Snow two stroke oil premixed. The Citgo Sea and Snow two stroke oil is one of the better products on the market and is actually one of the less expensive. We go thru gallons of the stuff in the winter in sleds and it works excellently. No reason to go leaner on oil as many studies prove that the more oil the better for HP basically. Just remember that if the carb is running premix then changing the premix ratio will change the A/F ratio the engine is running at (oil replaces gasoline in the jet so more oil equals less fuel and a leaner mixture) so you have to set the carb up on the premix ratio and stick with it. Believe it or not.....I have done some "research" on this with mod'ed weedeater engines....LOL. You should hear my leaf blower run. It is the envy of the neighborhood.

I couldn't agree more that it pays to by gas from the majors. In another life I worked at a refinery and I screwed up my share of gas and oil and believe me, there's a thriving market for low priced off spec product. The majors don't sell it at their own stations but they damn sure sell it. We had a guy who specialized in selling it and the Habib's type gas & liquor stores line up to buy it. Even now in my current incarnation I just sold 25,000 gallons of 10 year old #2 diesel fuel to a major distributor (not a refiner) who just blended it in with their stock. Buyer beware.

That's just great, you crushed my faith in the oil industry in one fell swoop!! Thanks

 

[jestal]

Even at the majors you would not believe what has shown up in gasoline over the years. Heavy doses of silicones, peroxides, etc. are not unheard of. Gasoline is very unregulated..... Peroxides, BTW, are what makes "sour gas" smell sour. That crudy stuff that is in fuel tanks in the junk yard that have been sitting for years....somehow shows up in commercial fuel occasionally. Must have been sitting somewhere for quite awhile. Even the major's stations are independent businessmen so they can dump anything they want into their tanks so it is a bit of a crap shoot.

 

[panthercity]

Yuppers. I was working a fuel spill a while back at a Shell station. While we were there, a tanker pulled in to the Exxon across the street, topped off their tanks then came over to the Shell to do the same. The two stations are owned by the same fellow.

Watching the local Pride distribution tank farm, we see all manner of tankers come in for a load. Very few of them are branded.

 

[FJRski]

There are a number of other posts where this topic is discussed to EXHAUSTion. Based on what I read there, I switched from premium to regular, saw my gas mileage actually go up when I switched to 87 octane, with no discernable decrease in performance.

 

[Bugnatr]

87 is fine. Once in southern Utah I put in 85 by mistake. The FJR does NOT like that stuff. Mixed in some 91 and she ran just fine.