TL-QT

Ok, I'm thinking of getting and upscale car like the TL but I'm kinda stingy on the gas, I don't wanna pay the extra money for 91 octane. I'm wondering what would happen if I used 87 instead. Would it kill the car somehow? I know it losses power, does it loss milage per gallon too? Has anyone only used 87 with cars recommended for 91 on a regular basis. The specs say 91 is recommended not that I have to use it. I know some people out there are thinking someone buying a 40k can $ car and not paying for the recommended gas is stupid but it will play a big factor if i'm getting this car or not. Thanx a lot

AzNTL

i would suggest you get preium. regular loses mpg and in addition makes ur engine dirty b/c it doesnt clean as well. preium increases mpg (not by much say around 10 - 20 miles) and is a lot better for your engine in the long run. and think about this you will only save a buck or 2 if u get regular. its not like $5 - 10 that youll b saving. HAVE FUN WITH YOUR TL and its BETTER for you TL as well

Malcolm

Actually, it is possible that the loss in mpg will result in you refilling the tank so frequently that you will end up spending more money on gas!!! Of course this depends on the price difference between premium and regular.

Malcolm

Actually, it is possible that the loss in mpg will lead to refilling the tank more frequently to an extent that you will end up spending more money on gas!!!

Bitium

I don't think it would make a difference, since a higher octane is used on high compression engines because the higher the octane the less chances the fuel to ignite with compression. Like a supercharger, you have to used 93 octane or higher. My friend that has a 857hp Lexus and he has to put 110 octane or higher on his car. The octane rating of gasoline tells you the amount that the fuel can be compressed before if spontaneously ignites. When gas ignites by compression rather than because of the spark from the spark plug, it causes knocking in the engine. Knocking can damage an engine, so it is not something you want have happening. Lower octane gas (like "regular" 87 octane gasoline) can handle the least amount of compression before igniting. So by putting 87,89,91,93 octane gas WILL NOT INCREASE OR DECREASE HORSEPOWER AND IT WILL NOT INCREASE OR DECREASE MPG. Hope this helps.

matt7184

If you really dont want to use 91 octane, go buy some tolulene in bulk and mix your gas. You can have as high an octane you want, but you only need 91-92.

Mr Hyde

Actually in my car which has a higher compression, too low of an octane will trigger knocking and the knock sensors will kick in retarding the timing. It wont retard it right to the edge of knocking but will go even further to be on the safe side and that will decrease power and mpg, but there shouldnt be any engine damage as that is the whole reason for having knock sensors.


Will you damage the engine; probably not
Will you be running at peak efficiency; again probably not.

TL-QT

Well there is a big price difference. Reg is about 68 cents/litre (live in canada) and premium is about 10 cents more/litre. Each fillup is about 50 litres so that equals about an extra 5 bux or so. Lets say i fill up twice a week, thats 10 bux each week times 4 for each week in a month. Total is at least 40 bux a month spreaded over time. Thats just a estimate cuz i think i'll be filling up about 2.5 times a week. Thanx for the help, I think I can stick w/ regular if it doesn't lose much power and mpg stated above.

If n e one can back it up it would be appreciated.

Guest

I think he was talking American money here I'm not quite sure how much a Canadian dollar is worth, but I know it's less.

~Frankie

TL-QT

Yea I kno he was talking about us dollars. but its still the same point, u spend it where u make it so it evens out.

liutang

She should not be buying the TL if the gas is of any concern. It's like going to a concert and complaining the music is too loud.

NSX4dr

I disagree........

I have a friend who has a Single Turbo Supra (687hp@wheels) and he can run standard pump gas but makes less power.
Ask your friend he'll tell you............Dyno proven

Our cars automatically retard timing when detonation occurs, therefore no detonation, more power..........USE 93

TL-QT

Loud music doesn't cost an extra 5 bux each time 2.5 times a week.

SilverStreak2kTL

yea, analogy is a little off, maybe like buying a nice camera but stinging on the film?

TL-QT

Actually nice camera, cheap film. LOL

matt7184

He is correct, octane is only a rating of resistance to detonation.

Do you know why he makes less power with lower octane gas? It's because he is running lower boost. If he put his highest boost setting at 92 octane and then runs the same boost setting with say 100 octane, his power will be the same. By running a higher octane, he can run more boost, so he will get more power. The power here has nothing to do with the gas he is running, it's the amount of boost he is running.

NSX4dr

So then if you can't make more power w/o any adjustments, Why do they make Octane boosters...?

I've seen dyno printouts of cars w/ octane boosters increase in power just w/ that item........

Read your own comments.......

Octane is the resistance to detonation, hence higher octane less reduction in timing, therefore increasing power........no?

Bitium

The compression ratio of your engine determines the octane rating of the gas you must use in the car. One way to increase the horsepower of an engine of a given displacement is to increase its compression ratio. So a "high performance engine" has a higher compression ratio and requires higher octane fuel. The advantage of a high compression ratio is that it gives your engine a higher horsepower rating for a given engine weight - that is what makes the engine "high performance". The disadvantage is that the gasoline for your engine costs more.

The name "octane" comes from the following fact. When you take crude oil and "crack" it in a refinery, you end up getting hydrocarbon chains of different lengths. These different chain lengths can then be separated from each other and blended to form different fuels. For example, you may have heard of methane, propane and butane. All three of them are hydrocarbons. Methane has just a single carbon atom. Propane has three carbon atoms chained together. Butane has four carbon atoms chained together. Pentane has 5, hexane has 6, heptane has 7 and octane has 8 carbons chained together.

It turns out that heptane handles compression very poorly. Compress it just a little and it ignites spontaneously. Octane handles compression very well - you can compress it a lot and nothing happens. 87 octane gasoline is gasoline that contains 87% octane and 13% heptane (or some other combination of fuels that has the same performance of the 87/13 combination of octane/heptane). It spontaneously ignites at a given compression level, and can only be used in engines that do not exceed that compression ratio.

mikester

Using the numbers you posted, you would be paying about $650 CAN extra per year, if the gas mileage is equal. However, on every vehicle I have owned, I have observed that the gas mileage is about 10% better with the premium fuel.

So, if you factor in the better gas mileage, that means you would have to fillup about 2.75 times per week with regular vs. 2.5 times a week with premium. Running the numbers using these figures, and the difference shrinks to $208 CAN per year! That's nothing!

If spending an extra $200 CAN a year to buy fuel for a $40k CAN vehicle is something you don't want to do, then by all means buy a different vehicle. I don't see any point in buying a vehicle with this kind of performance and then impairing its performance to save a few dollars on fuel. Also, consider the fact that the higher octane fuels also have more detergents and additives to them, so you won't accumulate as much crud in your high-performance engine, which I think would prove beneficial if you plan on keeping the car for a long time.

Bitium

I know one thing about money and gas:

I have spend $4,782.31 on Gas in a year and 7 months.

black2000

Since we've got a "regular vs. premium" thread going, and only one person responded to this question the first time I asked it, I'm gonna repeat this:

I've never heard this before, but I wanted to check this out with my knowledgable colleagues here:

My wife was told by a guy at a gas station that using lower octane gas (87) than recommended (91) will result in the premature failure of the TL's catalytic converter and other emissions equipment!?!

Is there anything to this?

Thanks,

StylinTLS

Well...on the bright side. If your cat ever gives out, you have legal reason to get a high flo cat.

Bitium

NO

stevebo

So by putting 87,89,91,93 octane gas WILL NOT INCREASE OR DECREASE HORSEPOWER AND IT WILL NOT INCREASE OR DECREASE MPG. Hope this helps. [/B][/QUOTE]

I agree with you in prociple, but if you use lower octane gas, the engine starts to ping, the knock sensor retards the timing, and you get less HP for the same amount of throttle position. Therefore you need to give more gas to go the same speed and finally you get less mpg because you used lower octane gas.

:-)

liutang

Buy the TL, and use regular gas. Enjoy what you can and don't worry about it. Cars are cars. Unless you really worry about performance or longevity, then gas doesn't matter. Sounds like you just want a nice car to cruise around for a while so pick whatever gas you want and be happy about it. Hmm... notice a trend. Whatever makes you happy. If spending extra $$ on gas makes you feel better, then do it. If it doesn't, then don't do it. Octane won't really matter in this car. A 687hp Supra, might be different, but let's face it, the TL is no 687hp Supra and it never will unless you strip the shlt out of it and do some engine swap or something. So, what octane to put into your TL is a mute point. Use whatever makes you or your wallet happy.

Bitium

That's because the engine it's making modifications that results in more or less HP/MPG. Like you said "Because you used lower octane then different results. Not beacuse is a lower or higher octane.

stevebo

So I guess we are in violent agreement... :-)

TL-QT

Yup this is totally my point. I'm not really trying 2 be stingy on the gas but more of sumthin nice to drive to point a to b. I'm not hardcore speed junky that needs to get to the next red light b4 the car beside me does. Just get me 2 one point to another. Isn't that wat the TL is meant for? cuz it definitely isn't a screamer.

iatacs19

hey, SilverStreak2kTL do you go to Cornell?
I just graduated this year... nice TL.

Malcolm

I spoke with an Acura dealer and he said 89 Octane is fine. So if you are looking to find a cheaper substitute for 91/92/94 and still get better quality than 87, use 89

ACTUP

I just want to be clear on some points. I use no less than 93 in my TL, are you guys saying there are no long term effects to my cars engine if I were to use 87 on a regular basis? My manual says the TL's engine will compensate for the lower octane but you might experience some pings or knocks, how can that be good for the engine long term?? Some clarification please...I've read the posts about compression and pre-ingintion but isn't that bad for the car if it continues for let's say a year or two.

Bitium

Like Mr. Hyde said:
Actually in my car which has a higher compression, too low of an octane will trigger knocking and the knock sensors will kick in retarding the timing. It wont retard it right to the edge of knocking but will go even further to be on the safe side and that will decrease power and mpg, but there shouldnt be any engine damage as that is the whole reason for having knock sensors.

But then I add, thats the reason of having knock sensors. The sensors are there to determine when it happens and ajust to it to get rid of knoking. Some knoking will still happen before the engine will self adjust. Since the engine retards the timing this will result in less efficiency. So is not recomended by ACURA. Are you safe to use 87? I would guess YES. Will it damage the engine in the long term, Don't know.

ACTUP

Thanks for the response....My conclusion is this; since there is no difinitive answer on long term damage to the engine using a lower octane over a long period of time, the money saved using a lower octane may just be needed for engine repair...so why take the chance? I don't think the savings are substanial enough to risk potential engine damange. But to each his own, 87 - 93 you have the right to choose.

happy happy joy joy

matt7184

They were trying to get you to spend more.

TL-QT

Well now if i were 2 choose which fuel grade to take. I'd go with the 89 to be in the middle. Acura did not reply to my question but Bmw did, they say 91 is wat they use to test the cars, but 89 and up is recommended.

Gomez

Problem is, the car calls for 91 but you can only get 87, 89 or 93 here in Texas. Sometimes I mix 89 and 93, but it's a pain in the butt so I usually just pony up for the 93.

I usually buy my gas at Sam's Wholesale, and the 93 is only $1.55US or so right now.