I never noticed a rotten egg smell, but I did notice a slight knock when using anything under 91 grade.

However, my previous car had a faulty catalytic converter and I did notice the smell then. S PAW 1 is right on the money.

 

Cheveron Mid grade. I notice everything about my car and I tried shell, 76 and chevron is usually the best for performance.

 

Is there anything wrong with switching from different gases when filling up?

 

Why does it matter if you JUST use what that manufacture recommends? PREMIUM!!!!!

 

What Acura recommends doesn't take away from my curiosity

 

Hey RockOut, that's pretty interesting what you found about Amoco. I agree with you though, just because BP isn't part of this 'Top Tier Gas' doesn't mean they don't have good fuel. I've always liked Shell (since I started to drive, probably had something to do with the fact I earned points with my Shell card ) so I was glad to see it's part of this program that Acura recommends...

 

see that's what i thought too....but i filled up my tank today w/ v-power and well...i'm disappointed. feels like chevron gives more kick...BUT the weird thing is that the trip computer read greater than 468, as apposed to the greater than 350 i get with chevron (i think it's 350....). thoughts?

 

The Chevron pump kicks off sooner...

Me and my dad have done tons of testing of different brands of gas (all premium)in our turbo cars before we started running only 100LL from the airport.

Texaco gave best results with Chevron a close second. I don't remember the rest of the list because I haven't used pump gas in a long time.

The cars were monitored with the laptop and tuned to the max for each brand of gas until we got knock retard. Typically we could run an extra pound or two of boost with Chevron and Texaco meaning the octane was a tad bit higher even though they were all rated at 92 octane. There were some, however, that it seemed like they ran 87 octane in their 92 pumps.

 

91 octane; either from Shell or Chevron.

 

91 mobil, 76

 

Put anything you want in your ride, it's up to you. I only slightly lean toward the premium since it's listed in the owner's manual, however though it shouldn't harm the engine to go any less. I did come across a USA today article how they dispel the myth of premium fuel (wish I saved the link). Today most if not all sophisticated engines can run under reg octane fuel with insignificant mixed results. I guess it's a matter of opinion and the "placebo effect" of rendering your car the proper dosage of octane. I have tried all fuel grades and nothing was significant to mention, I still got my usual 23-24 avg mpg's, and no noticeable change in performance. Then again I didn't have my stopwatch handy and a closed track to record to the tenth of a second. Fill 'em up with whatever octane you choose!

 

Shell V-power.

 

91+ octane and preferably a toptiergas brand. I have personally noticed better throttle response with Shell and Chevron

 

Ever notice how when you finish washing and waxing your car it goes faster? How about when you put on new tires? Putting in a higher grade of gas works the same way. Its called the Placebo effect.

Chemically, a higher grade of gas cannot give you more power under normal conditions, its like your car going faster because its Friday.

That being said, it IS possible under certain circumstances. If your injectors are clogged or you have some other serious deposits in your engine, a grade of gasoline that has a solvent in it might help clean your car out a bit and make it run better. But if thats the case your MUCH better putting a bottle of cleaner in. I recommend Techtron concentrate, but they are all pretty much the same.

For those of you that think a better BRAND of gas has an effect, you are completely deluding yourself. The way gas works is a big honking ship comes in, drops off several million gallons of gas at a huge tank, and the tanker trucks line up and get filled, out of the SAME tank, then they drive to whatever brand name station they are going to and drop it off. Sometimes the stations have individual addatives they use, but that is not generally the case. In any case the gas itself comes from the same place, no matter what station you go to. Now, there may be specific stations that are doing bad things to their gas, their tanks may allow water in or whatever, but thats not a brand thing thats usually got more to do with the station itself.

 

Use BP Amoco. Packers use cheez whiz in their tanks.

 

must use premium..says it on the gas lid..must use. comes out to like 2.00 more per fillup.

 

Premiun 91/93 octane nothing else

 

Nothing but 91 octane, nothing but Chevron.

 

Not true. Why not run 85 if your theory is correct? We have an 11:1 motor and 91 octane is already pushing it. 87 octane may have more energy than 92 but when the computer is pulling 10 degrees of timing out due to detonation on 87, you lose power and mileage. You will lose power on the cheap stuff period. Ever feel the car surging on cheap gas? That's the computer pulling timing and putting it back in.

Brand of gas does matter. I've proven it.

 

man this is really interesting, i've never seen this before. it does all come from the same place but chevron and shell have proven to have the top additive packs on the market. this is also why these 2 brands are generally more expensive than the rest.

 

I hate Cars:
"Not true. Why not run 85 if your theory is correct? We have an 11:1 motor and 91 octane is already pushing it. 87 octane may have more energy than 92 but when the computer is pulling 10 degrees of timing out due to detonation on 87, you lose power and mileage. You will lose power on the cheap stuff period. Ever feel the car surging on cheap gas? That's the computer pulling timing and putting it back in."

ARRRRG I hate it when people dont read your post, then try to disagree... I will try to highlight some of the more important words. Read the second paragraph of my post: CHEMICALLY, a higher grade of gas cannot give you more power. I will say it again CHEMICALLY!!! It is not my theory that YOUR CAR will run better on lower octaine, it is chemical FACT that the lower the octaine the more explosive power gas has. If you disagree, you need to get yourself a chemistry book and check how gasoline and octaine work. Let me sum it up for you: octaine makes gas more stable, therefore LESS explosive. There is a 1:1 correlation between less explosive and less power.

What that means is there is more POTENTIAL power in lower grade gasoline. IE if you explode the same amount under the same conditions the lower grade gasoline will return MORE power.

Now let me break down the REALITY for you. If the car is set up to take a higher grade of gas, it can ARTIFICIALLY be used to return higher power. The way it works is the higher octaine allows a more controlled explosion allowing higher compression levels and more explosions per second. You could run a lower grade gasoline, disable the knock sensors, and you power would blow off the charts, of course your engine would do the same shortly thereafter.

The point is: if your car is set up to run on 91, it will run best on 91. Putting in 93, 95, or 200077744 grade octane will NOT improve performance on a car set up to run on 91, unless the car does dynamic tuning, (like the SAAB) which the Acura does not, or unless you are mapping the computer manually for a higher grade of gas, you will not have an effect using higher grade gas than the engine is designed for. If you make some engine upgrades you can make your engine work better on a higher grade of gas, thats what the car designers do, they figure out what grade they want to use and tune the engine around that.

"Brand of gas does matter. I've proven it."

Again, we are not in complete disagreement, only as regards Acuras. You claim to have tested brands of gas on a highly modified 602 HP engine. My acura is a 258Hp NA engine, its not quite the same thing. I dont disagree that brands of gas may have slightly better or worse additives. You might be able to tell a slight difference in a highly modified car, but unless I'm mistaken, most of the people here are running the NA Acura engine, not the twin turbo GN engine. Saying something like " I run kerosine in my helocopter and it kicks ass" dosnt seem to have much bearing on what you do with your Acura. The gas itself however comes from the same place. But on an engine like the Acura has if you can feel a .000003% increase in Hp I'll eat your tires. Its pretty much the same as saying "i just washed the car and lessened the weight by 0.2lbs (on a 3K lb car), so I'm going to go faster because the car is lighter because of the weight of the dirt I got off. Or saying that the coefficient of friction has dropped by 0.00005% because I just waxed the car and it slides through the air better." Both of these things are technally true, but you would need a really SEROIUS computer to be able to tell the difference, and if your ass is that sensitive a computer, you should be working for NASA not wasting your time posting here.

You also fail to take into account that since the addatives are usually added at the STATION, that it does not make Texico a better brand, it makes your specific Texico station a better station. See the difference? A station in California might add different things than one in Massachusetts, or one in Virgina, or one 3 blocks away.

I dont doubt your tests, I seriously doubt your testing proceedures. Dont they teach kids anything about science nowadays?

 

Got to hurry, going to the UFC...

Ok, the Texaco station and Chevron station in my town are better than the rest. Happy?

Yes, as I stated, lower octane usually, but not always = more power as long as there isn't detonation. BUT.... Once you start pulling back timing to avoid detonation, you lose gas mileage and power. Our 11:1 motors will fully take advantage of 91 octane. At least mine will since I occasionally hear a ping here and there on it. Could probably pick up a hp or two going to 92 but I drive it like an old man anyway.

Believe me, I spent hours on my two hour trip to work playing with fuel, timing maps, and octane trying to get the best gas mileage in the other car and I was able to knock down an occasional 29mpg which was a few mpg better than stock. I'm well aware of the correlation of octane vs timing vs mileage vs power.

 

I use 91... good gas.

 

Why do we argue about this?

The higher the OCTANE (RON) the LESS volitile the gasoline. PERIOD.
That means the higher the number the less responsive the gas is to ignition sources. It's harder to ignite the A/F fuel mixture.

Please be aware that octane DOES NOT control the burn rate of the A/F mixture.

You will always make more power and better economy on the LOWEST octane you can run without knocking or retarding spark timing. If you require 91 octane, use 91 octane. If you need 116 octane...guess what happens if you use 87 octane. It's a long walk home.

The more octane you use when not needed the more money you waste. Engine controls cannot detect octane except for some very exotic one off prototype cars from OEM. Most cars use the knock sensor (IF THEY ARE EQUIPPED) to determine if the engine has enough octane to keep the desired spark timing in the engine.

If the knock sensor trips, timing is pulled. On a supercharged engine, 1 degree of spark timing can be worth 4-5 HP and 8-10 lb.-ft. of torque. Pull out 4 degrees of spark and poof you are down 20 HP and 40 lb.-ft. of torque. The reverse is true (to an extent as there are limits to spark advance) add spark timing without knock and more power can be had.

Higher octane fuel is less likely to ignite so it is required with supercharged, turbocharged and high compression ratio engine. Supercharged and Turbocharged engines are almost always knock constrained.

Octane DOES NOT add power to an engine. I cannot understand how people can say their cars made more power with more octane. Octane does not add power.

What determines power output of any gasoline engine is how efficiently it burns fuel. Air is a limiting factor in power production.

So your TL requires 91 octane fuel...USE 91 OCTANE. Do not bother with 93 or 94 and don't even consider 100 unleaded race fuel. It's a waste.

Using 89 or 87 octane will almost always dip into the KS strategy. Will the engine run on lower octane...yes. Will it make more power...again since the design requires 91 octane...you will lose power when the spark is removed.

I doubt you will notice a change in fuel economy since most of the driving will be Part Throttle at 14.64:1 A/F ratio. If you go WOT, power will change but economy goes out the window anyway.

A-Train

 

Best Answer so far.

 

I completely agree, what I should have done is stated specifically that using a higher grade than recommended is useless, while using lower than recommended will cause the engine to perform poorly. Thats what I was trying to say, guess I didnt say it all that well I am an engineer not a politician.

 

I heard that all gasoline (at least in California) is regulated to contain the exact same detergents, so it doesn't really matter which gas you get, as long as its 91? Lets not get too specific with how much customers each gas station has, how old the pumps are, how long the gas has been sitting there, etc.

So lets assume you take 91 octane from a Chevron station and 91 octane from some no-name station. They both use the same exact pumps, have the same amount of traffic, etc. Will the gas be the same from both stations?

 

What differentiates gas stations from let say Chevron from Shell is the additives that they put into the gasoline.

Chevron = Techron
Shell = VPower

If you ask me, I can't really tell a difference in my TL although my car seems to get better mileage with VPower.

I still like Chevron just because it tends to be a bit cheaper and more accessible.

 

V-power alllllllll the waayy,
i really could feel the difference very smooth and beautiful sound

 

Wow, nice post! thanks for commenting, I am really learning alot about the finer details on gas and the octane levels!