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Gas-- Premium? Does it make a difference

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Old Sep 26, 2008 | 08:24 PM
  #21  
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67mustang302
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Working at a refinery I can tell you there is a difference between fuel blends in differing octanes. So here's a small fuel lesson...


The difference between lower and higher octane levels is not merely it's detonation resistance. As was mentioned previously, higher octane fuels are more completely refined. Lower impurities that cause deposit buildup, and lower impurities that also cause combustion to be inefficient.

Also understand that fuel blending is not simply taking gas and just adding a couple cleaners to it. After the fuel is refined it then goes through a blending process, in which a series of differing chemicals are added. Some of them are to help with detonation resistance, others are to help with combustion flame front speed, others are to assist in even vaporization and so on and so forth.

What this means is that quality higher octane fuels will often burn more completely, more cleanly and be more stable while doing it. Now it's not true for every vehicle as engines differ and fuel quality in given regions differ, but generally speaking, lower octane fuels have more crap in them and don't necessarily burn as completely, simply as a result of the blending components.
Old Sep 26, 2008 | 09:53 PM
  #22  
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Well, bottom line.. if you have the $'s to blow on premium gas for your car then go ahead & spend it. If all it does is makes you THINK you're getting more power or economy then horrah for you

Chances are a modern ECU equipped engine will recognize the higher octane fuel and probably WILL do stuff like advance the timing a bit in order to use the better fuel more effectively. Personally I'd think the difference at the drag strip would be measured in 0.001's & no more. And maybe with premium gas you might get an extra 5-10 miles of range improve fuel economy. But nothing more major than that.

Whatever floats your boat
Old Sep 26, 2008 | 10:05 PM
  #23  
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Originally Posted by GreyStang
Well, bottom line.. if you have the $'s to blow on premium gas for your car then go ahead & spend it. If all it does is makes you THINK you're getting more power or economy then horrah for you

Chances are a modern ECU equipped engine will recognize the higher octane fuel and probably WILL do stuff like advance the timing a bit in order to use the better fuel more effectively. Personally I'd think the difference at the drag strip would be measured in 0.001's & no more. And maybe with premium gas you might get an extra 5-10 miles of range improve fuel economy. But nothing more major than that.

Whatever floats your boat
The thing about premium is its not a matter of $money$ to blow on it.. If you have a 15 gallon tank then you'll spend around (at least where I live) $1.50 more for a full tank of gas.. A $1.50 isn't gonna kill me...
Old Sep 26, 2008 | 10:08 PM
  #24  
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Again though, it's not necessarily a power or mileage issue. Premium is just a higher quality fuel that causes less problems in the long run.
Old Sep 28, 2008 | 02:46 AM
  #25  
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Originally Posted by 67mustang302
Again though, it's not necessarily a power or mileage issue. Premium is just a higher quality fuel that causes less problems in the long run.
I fail to see why this is so difficult to understand. I've had ALOT of people try to argue with me about this, and I say the same thing and they actually think that some gimmick octane booster is going to make up for fuel that has been meticulously refined, because we all know throwing some mixer in your tank is going to make things any different. If that were the case, I guess we would all be buying crude gasoline and just throwing a mixer in there because that's essentially what they're saying.

If you could, could you PM me an indepth explanation. I would greatly appreciate it, as I like to learn about this stuff on a more indepth level if at all possible, and you apparently have the experience to talk about it (this is assuming you have the time, and actually want to. If not, that's okay too). Not to mention I'm seriously tired of my dad sending me emails about octane boosters and how MSN says they are supposedly "economical!" when really they're just a waste of $1.50 that you would've saved. My dad is overly persistant because he wants it to be his way, and I've actually been looking around for a good source of info on this for awhile so I can slap in on his desk and tell him to shut his trap about it already.
Old Sep 29, 2008 | 05:15 AM
  #26  
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Originally Posted by DeltaElite121
I fail to see why this is so difficult to understand. I've had ALOT of people try to argue with me about this, and I say the same thing and they actually think that some gimmick octane booster is going to make up for fuel that has been meticulously refined, because we all know throwing some mixer in your tank is going to make things any different. If that were the case, I guess we would all be buying crude gasoline and just throwing a mixer in there because that's essentially what they're saying.

If you could, could you PM me an indepth explanation. I would greatly appreciate it, as I like to learn about this stuff on a more indepth level if at all possible, and you apparently have the experience to talk about it (this is assuming you have the time, and actually want to. If not, that's okay too). Not to mention I'm seriously tired of my dad sending me emails about octane boosters and how MSN says they are supposedly "economical!" when really they're just a waste of $1.50 that you would've saved. My dad is overly persistant because he wants it to be his way, and I've actually been looking around for a good source of info on this for awhile so I can slap in on his desk and tell him to shut his trap about it already.
I don't recommend octane-booster additives for your tank. I ran octane-boost through an engine and pulled a plug and it had brown gunky build-up on the plug that was NEVER there before I added the stuff. With my experience (16-years of ASE certification, and PLENTY of experimentation) One should use the highest octane available at the every-day pump (91-93) and the only additives that work for cleaning is Techron, and STP also makes a good product. Don't use additives for anything except cleaning, period. Good luck with the Dad. Yes, more octane is good if the fuel was formulated with it in it already. All you're doing with additives is mixing a cocktail that may or may not work. Ever heard the term SNAKE OIL? Don't fall for it, just use good fuel and keep things clean and call it good.

If you want MORE octane it's really not necessary for a factory engine but try it for yourself. Go to 76, Pacific Pride, or Sonoco Racing Fuel stores and you can fill up at their 110 octane pumps, or buy a 5-gallon drum of the stuff. Sorry, you're not going to get pure octane in a can and I would question anything that claims it will actually mix with your fuel and work.

Last edited by bwkelley76; Sep 29, 2008 at 03:36 PM.
Old Sep 29, 2008 | 10:15 AM
  #27  
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Are their any tunes available for a 94-95 5.0L?
Old Sep 30, 2008 | 12:18 AM
  #28  
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Hmm after reading a PM I just got I can safely say this subject is split 50/50. So many people saying its better because of this, this, and this, others saying its worse/a waste because of this, this, and this.

If I had $100 to spare I would take a day out and test some of this.
-I would fill up a full tank with normal unleaded gas. Then drive 1/2 the tank on highway, and then drive 1/2 city...then record the results (mpg, etc.)
-Then I would fill up a tank with Premium and do the same. Drive 1/2 city and 1/2 highway and record the results (mpg, horsepower changes, etc.)

Too bad I don't have that money, cause I'd sure like to try this out. I would try it out the way it is but the results wouldn't be accurate because some weeks I do 3/4 highway driving, other weeks I do no highway driving.
Old Sep 30, 2008 | 06:43 AM
  #29  
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Well, nice gesture maxshuty lol, but it's probably more complicated than that. Chances are if you've been running regular grade all this time, you probably need to go through a couple tankfull's of premium to flush out the old stuff & to give the ECU time to fully adjust to the higher octane. Heck in extreme conditions you might need to do an injector clean as well.

I dunno what's best, & probably there are many different scenarios of outcome depending on the vehicle. The BEST thing you could do if you REALLY want to experience a gain with an otherwise stock stang is to give it a "premium gas tune". That will push the engine settings significantly above what the ECU would do automatically and, you'd notice a big difference. The one problem though, you'd be stuck needing to use premium gas from that point on.
Old Sep 30, 2008 | 09:06 PM
  #30  
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Originally Posted by GreyStang
Well, nice gesture maxshuty lol, but it's probably more complicated than that. Chances are if you've been running regular grade all this time, you probably need to go through a couple tankfull's of premium to flush out the old stuff & to give the ECU time to fully adjust to the higher octane. Heck in extreme conditions you might need to do an injector clean as well.

I dunno what's best, & probably there are many different scenarios of outcome depending on the vehicle. The BEST thing you could do if you REALLY want to experience a gain with an otherwise stock stang is to give it a "premium gas tune". That will push the engine settings significantly above what the ECU would do automatically and, you'd notice a big difference. The one problem though, you'd be stuck needing to use premium gas from that point on.


BRAVO!!! Couldn't have said it better myself. As far as the 50/50 I do believe that the experienced folks as in the fuel-refinery worker and the ASE cert tech that is studying emissions systems would count for more than one vote. But I'm one of those 2 and am not going to stuff the ballot.

People want "Instant" results and unfortunately you have to correct the damage that the junk-fuel has caused, and get the vehicle and it's fuel system running clean again before you will see much difference. It's not going to be "Instant" in most cases. However, my GF who has 90k miles on her Mazda just filled up with 91 octane and we took a 2-day trip and the car got much better gas mileage than the last time we took the same trip a few months ago. Sorry, no numbers for ya. Just did the trip on one tank instead of let's say 1.5 tanks. Too many variables to give specific MPG, but definitely noticeable. Also her car didn't detonate once, and it had been doing that prior. NOTE: Detonation is from carbon and could be the result of running crappy gas for some time. (Thank goodness she's seen the light)



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