Gas Octane

yeah what they said

 

If you have ever been to a gas station where all the pumps are really slow, it's because the filters need to be changed.

I believe there is a filter in the main tank, then one at each pump, and that is before it gets to your vehicle.

With that said, I avoid mom and pop gas stations, they are less likely to keep up on maintenance then the larger companies.

 

Back on the subject of octane, I have been running 91+ in my truck since June 2010. In June of 2011 I plan on switching back to 87, and will continue to run 87 unless I get pinging going up small hills, or at certain RPM ranges.

I would say my most consistent driving is on road trips with the Cruise Control set. I will have a few places to compare data. If the cost per mile goes up on 87, or I get bad pinging while driving uphills, I will switch back to 91 and stay there. At which point I may as well put a super charger in

 

JWC and Infinus pretty well beat this argument to death until in posts #458 and #459 they virtually agreed and apologized to each other. The upshot was that there are no or very little gains if any to using fuel of an octane rating higher than an engine is designed for; i. e. you are wasting your money buying 91 when your vehicle only requires 87.

From Wikipedia: 'A common misconception is that power output or fuel mileage can be improved by burning higher octane fuel than a particular engine was designed for. The power output of an engine depends in part on the energy density of its fuel, but similar fuels with different octane ratings have similar density. Since switching to a higher octane fuel does not add any more hydrocarbon content or oxygen, the engine cannot produce more power.' The article continues and lists qualifiers and other variables, but that is the essence of it.

 

i use 87 because I am a cheap mofo

 

I don't know where you guys live where the price difference between 87 and 91 is only $.15 a gallon everywhere around here it's 32-35 cents more per gallon.

 

yeah man, exactly.

 

sorry, my bad, in las cruces reg is 2.89 and 91 is 3.03..... oh, and I just spoke to my bro who works for western refinery in albuquerque, he said no about those "churning blades", that there are pumps just like a fuel tank, the tanks are just big steel tanks in the ground,,,,,, he installed some in a gas station off alameda just 2 years ago, and that they are very suceptable to corrosion and water leakage.

also, yes though there are "filters" on the line he said they are very poor quality..... and that the reason sometimes the pumps work slowly is yes they may be clogged up a bit, but mostly is due to temperatures,,,,, notice how they almost never do that in the summer, but in the winter they are like molasis.......

also, DONT TRUST WIKIPEDIA, I could post something saying Former Pres. Bush built the Pyramids and get it posted to that site.

I have a solution to this issue.... do some actual research, talk to some Master Technicians at more than just one dealership, and maybe use a bit of logic..... like this....
I havent changed my oil in 2 years.... or filters..... do you think i will get better gas milage with 91???? probably not since your motor is running like crap anyways that the difference will be so slight its not noticable.
or:
I have a 1990 Toyota and i use 86 and it runs fine, but my 2010 runs like crap with 86...... DIFFERENT TECHNOLOGY MEANS DIFFERENT PERFORMANCE!!!!!!!!!!!!
DIFFERENT ELEVATION, DIFERENT MILAGE, DIFERENT TIRES, DIFERENT CARGO, DIFERENT DRIVING STYLE......... i am suree if we were all robots and had the exact same controlled enviroment and were in a lab i bet you could see the difference between the gas easily, but since we dont,,,,,, its a never ending argueable dilema,,, i bet if i rolled my truck in neutral down a hill with 86 in the tank i would get better gas milage that a truck on a level road with 91........ THINK ABOUT IT!!!!!!

 

well, I guess it comes down to pure logic and reason. but heres what I have found through my own research and personal experiences...

i never fill up except for at Cheveron or Shell
i never fill up with anything but 90 or 91
i never fill up until at least a day after the 2 main places i fill up have had their refill.... i ask the supervisors for the schedules.... they give me the normal days but they are off by a day sometimes.
i stay ontop of maintenance to the t... oil changes w/ sythetic castrol or amsoil every 3500 miles, ff change every 15k miles, tires rotated and balanced every 3k miles, air filter ever oil change, case fluids every 15-20k
CHECK the plugs every oil change, SEA FOAM OR

$25 BG 44K Fuel System Cleaner Power Enhancer 11oz.

BG 44K the tank before i change the ff.

the only thing i really never look at is the O2 sensor- i try to change those every other year though.

 

I will agree with your remark about Wikipedia when I see your article there about Bush and the pyramids.

I'm curious about a couple things you've written:

1. What do you mean by 'actual research?' The example you give seems more like soliciting testimonials?
2. Does using multiple exclamation marks (let alone one in a simple declarative sentence) enhance what you call logic?

I'm only asking because I want to know.

 

yes Dan, !!!!!!!! make it more logical, I will get that on Wiki also. lol

I mean actual research because I have done tjust that. Its easy, go to google, type in Octane Research and stuff like that and read up on how the reaction of fuel in the combustion chamber differs with different octanes.

After that, kinda use general common sense with regard to maintenance of vehicles,,, if your air filter is 10 yrs old and you live in the desert your probably going to get less air through it than a new one.

-if you like in Denver, your going to get less air to your motor than a guy in San Diego,,, now thats where EFI v. Carb comes in play,,, new v. old EFI systems, ect.

elevation does play a role in fuel milage, vehicle year and maintenance services play a role, the temperature of the air plays a role, really EVERYTHING plays a role, thats why 2 ppl with the same vehicles, in the same city ect., can get 2 different gas milage averages.

Please, just one person do soome research on the inner workings of how fuel combusts and how the different octanes combust and post it.... that way its not me posting and you will just try to talk trash about it.

other than that, !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! I only use 91 due to having the TRD supercharger.

 

You haven't explained what 'actual research' is, or what you have done other than scan the web. I don't think you know what 'actual research' is. If you have a highly modified vehicle, than it may indeed run better with a higher octane gas; but then we are not talking about the same vehicle that was designed to run on 87, like a stock Tacoma.

You cannot do 'actual research' via google. You actually have to do do the research. And you have not answered how your multiple '!''s advance your argument.

You also use the term 'common sense,' another term you use without defining. I suggest that 'common sense' may be indistinguishable from 'prejudice' or 'myth' at least the way you use the terms.


If your definition of 'actual research' is to google the issue, try this from the Minnesota Dept of Commerce:

"• If your engine runs well and does not knock or ping on low octane gasoline, there is no advantage in
switching to higher octane gasoline.
• If your engine knocks or pings, it does not necessarily mean something is wrong with the gasoline. It could
be a problem with the engine’s electronic control systems, ignition timing or exhaust gas recirculation. On a
high mileage engine, a carbon build-up in the cylinders can increase cylinder pressures and cause knock.• Almost all of today’s new cars have fuel-injected engines that need to use gasoline with a detergent additive.
They do not necessarily need high octane gasoline with a detergent additive. Generally, new automobiles
need high octane gasoline only if the manufacturer recommends it.
• Always follow the auto manufacturer’s octane recommendations in your owner’s manual.
Octane Myths
• High octane gasoline improves mileage.
In general, if your car is designed to run on 87 octane gasoline, high octane gasoline will not improve
mileage. If switching to high octane gasoline does improve mileage, you might find that your engine, or its
control systems, need repair.
• High octane gasoline gives quicker starting.
No, it doesn’t.
• High octane gasoline increases power.
If your car is designed to run on 87 octane gasoline, you shouldn’t notice any more power on high octane
gasoline. Again, if it does make a noticeable difference, your engine, or the engine’s electronic control
systems, may need repair.
• High octane gasoline has been refined more – it is just a better product.
Additional refining steps are used to increase the octane; however, these additional steps do not necessarily
make the gasoline a “better” product for all engines. They just yield a different blend of hydrocarbons that
burn more slowly. The additional steps also increase the price."

or this, from Suffolk County, NJ:

"The advertising claims for these various grades would have us believe that the higher the octane of the gasoline that you use in your car, the better your car will run...more efficiently, cleaner, and with more "power." These are tempting claims.

The fact is that the overwhelming majority of cars on the road today do not need a high octane gasoline to run properly and efficiently. Octane ratings are a measure of a gasoline's ability to resist engine knock. "Knocking" or "pinging" in an engine results from an uneven burning of the fuel-air mixture. If your car is not "knocking," using a higher octane fuel will do absolutely nothing for you but waste your money. The fact is that regular unleaded gasoline, 87 octane, is the recommended fuel for most vehicles. You can determine what fuel is recommended for your vehicle by checking your owner's manual.

If you are using gasoline with an octane rating greater than 87 and your engine is not "knocking," drop down to a lower octane gasoline. If your engine begins to "knock," go back up to the next octane level. Remember, octane is nothing more than a measure of anti-knock quality...use the lowest octane fuel which provides you with knock-free operation.

Another myth is that use of a high octane fuel will improve fuel economy. The fact is that fuel economy is determined by a number of variables, including the energy content of the fuel and the condition of your vehicle, neither one of which have anything to do with the octane level of the fuel. In fact, two fuels of identical octane could have different energy content due to a difference in composition.

One last myth is that the name of the grade of fuel is an indicator of the quality or octane level of that fuel. These names should not be relied upon when you are choosing which fuel to use. The fact is that you should always choose your gasoline by checking the octane rating on the yellow sticker on the gas pump. By so doing, you will be assured that you are buying the gasoline that you want and, by using the lowest octane that still provides you with knock-free operation, you can save a significant amount of money on your gasoline purchases."

Of course if you prefer 'common sense,' prejudice, and mythology, to 'actual research,' have at it. The gasoline companies are happy to take your money and will probably be willing to endorse multiple '!'s' as a substitute for logic as long as you continue to pay them to say so.

I really don't mind your silly repetition of old octane myths, but when you claim your views are based on research and logic when you demonstrably do not have a clue about the meaning of either, you are at best unpersuasive.

 

I have a supercharger and premium fuel is required. I find that my Taco gets better gas mileage with Chevron than Costco gas.

Costco gas gives me between 2-5MPGs less than Chevron gas.

 

yeah, I have never really trusted Costco gas... although my buddy lives by Costco 91 in his Honda 954.

Me, I prefer 91 from Chev or Shell.

DanT: Thank you for doing research- "actual" is just what you did, not going off what your buddy says or what some other guy says.

"Actual" can also mean lab work or definative chemical break down.... I have actually done that in Chemistry lab at my college. A group project I was involved with broke down the molecular compunds of the 3 levels of gas from Shell. we found a difference in their detergents, addatives and explained how the Rm numbers are found. I didnt really understand most of it, but the group leader was a big time race car building guy and he did most of it.

some of those myths are false indeed, but some of them I would have to say with supporting modification (like the higher octane = better preformance) are totally concevable. But what ever, like I said people are always going to argue meanial issues and you have proven that.

But like I have said several times before, everything can effect gas milage, not just octane rating. Go back to my example of the car going down hill, if I put 91 in my truck and drove up hill and then 86 and rolled it down hill I bet I would get better gas milage with the 86.

 

here is just one of the sites which does a pretty good job at explaining Rm and why and how it is determined and its use.

http://www.csgnetwork.com/octaneratecalc.html

 

http://answers.encyclopedia.com/question/octane-number-determined-516622.html

 

http://www.faqs.org/faqs/autos/gasoline-faq/part3/ is a good site. It goes on to explain part of what you are saying, that there ARE other variables and one can experiment a little. Nonetheless, I contend that a stock engine in proper tune, and under normal circumstances only requires the gasoline the manufacturer recommends.

"If you use a fuel with an
octane rating higher than what the engine can use, you are just wasting
money by paying for octane that you can not utilise. The additive packages
are matched to the engines using the fuel, for example intake valve deposit
control additive concentrations may be increased in the premium octane grade.
If your vehicle does not have a knock sensor, then using a fuel with an
octane rating significantly below the octane requirement of the engine means
that the little men with hammers will gleefully pummel your engine to pieces.

You should initially be guided by the vehicle manufacturer's recommendations,
however you can experiment, as the variations in vehicle tolerances can
mean that Octane Number Requirement for a given vehicle model can range
over 6 Octane Numbers. Caution should be used, and remember to compensate
if the conditions change, such as carrying more people or driving in
different ambient conditions. You can often reduce the octane of the fuel
you use in winter because the temperature decrease and possible humidity
changes may significantly reduce the octane requirement of the engine.

Use the octane that provides cost-effective driveability and performance,
using anything more is waste of money, and anything less could result in
an unscheduled, expensive visit to your mechanic."

 

I agree with you that a vehicle IN GOOD TUNE only requires the octane the manufacturer recommends. Problem is that so far everyone on here is failing to look at the entirety of the question being asked and in what sense it is being applied. Thats all I have been trying to point out:
octane rating and gas milage is not ONLY dependant on manufacturer recommendation, but other issues as well such as tune, quality of gasoline ect.

thank you kinda getting what I was trying to point out. I didnt want to shove facts and things I know down ppls throats, I was hoping for someone just like you who would take the time to go and do some personal research on figuring out how fuel combusts, how diferent Rm and octanes and even brand of gas relates to gas milage and performance of that motor being fed that gas.

Its amazing how the small things make the big difference.

with that said, what do you feel about the gas you use: what kind do you use and octane?

 

have you looked on that thread about fuel additives? do you use any?

once in a while i use that horrible stuff NOS but if seems like it helps a TINY bit..... not as much as when I throw in 5 gallons of 101 vp unleaded race fuel other than that i use a can of

$25 BG 44k Fuel System Cleaner Power Enhancer 11oz.

BG 44k like twice a year and sea foam about twice a year as well.

 

lots of ppl seem to forget that 2008 and before tacoma manuals stated to use 91 octane for best performances. That means that the ECU was programed for 91, and may be still programmed for it even for more recent years (2009+).