I was wondering if anyone has tried using regular gas (87octane) in their TL's? I drive an 05 AT and put regular gas in the other day and did not notice a difference. So does it really matter or is it just a myth?

 

Yeah.....I used 87 octane, in the loaner car I get from Acura.

 

Do a search. In short, your car will run fine with regular. Reduced power, reduced gas mileage.

Had a neighbor who was using regular in an Infinity and had some problems. Brought it into the dealer and after inspecting the fuel injectors, the first they asked was "are you using premium?", he wasn't but said he was. They had to change out all the injectors.

Dave

 

if you must use regular, I'd advise adding in techron.

 

It will work fine....although prolonged usage could cause problems. At least thats what some other threads came to the conclusion of as I recall. Works fine for temp....but not recommended for the long term at all! Your knock sensor or something like this will adjust your motor to run ok....but again...not recommended long term.

 

why use regular, if you factor the cost difference and the mpg it works out to .01 to .02 cents per mile, are you really going to notice the cost, I think not so why chance damaging anything under the hood

 

but dont keep switching every time u pump gas

 

It really won't save you much money at all...just go with the premium.

 

Save a few pennies now, pay more in fuel injector additives and early replacement of injectors later.

 

Did you FLOOR IT ????


The premo gas is to prevent pinging from excessive chamber pressure. As long as you "baby" the thorttle, you will not have high chamber pressure (that is, premo is not needed if you "baby" the gas pedal).

Go out and WOT your TL with reg gas and get back to us....

 

Pinging is from pre detonation not chanber pressure .

higher octain burns slower, and colder (more controlable).

Boyles Law
PV=nRT (pressure * volume = number of moles of gas present * universal gas constant * temperature)

As you compress a gas, it heats up. As the air/fuel mixture heats up, it tends to explode without a spark. With a forced induction system, you also have heat soak from the turbo. Intercoolers help with this, but they're not perfect.

Higher compression ratio cars create greater compression (and power) by taking a larger volume of air and compressing it into a smaller space.
Forced-induction system forces a greater mass of air but compresses it less. However, since there are a greater amount of air molecules to react with the gasoline (which there will be more of if the system is "healthy"), you get a more energetic reaction.

You can also look at it a different way.
A higher compression ratio (say, 11:1), normally aspirated system starts off at 1 atmosphere (air pressure at sea level; 14.6959488 psi or 1.01325 bar) and compresses the air to maybe 11 atmospheres (161.6554368 psi!).
A lower compression (say, 8:1), forced induction system might start off with an additional 1 atmosphere (29.3918976 psi, from the turbo- or supercharger pressurizing the intake system) and only compress it 8 times it's original pressure. Of course, that's 235.1351808 psi!

It's all about how much air you're forcing into how much space. The more air forced into a smaller space, the more heat is generated and the greater resistence to pre-ignition you need.

Incidentally, a related concept is used to create refrigeration systems. You compress a gas and wick all of the heat away (basically, take thermal energy out of the refrigerant). Then, when you decompress the gas, it becomes colder than when you originally compressed it.

 

make up your mind. So, what is it ??? Hint = greater compression = high chamber pressure.

Another hint = what causes detonation ? = 1) carbon deposit glowing, 2) excessive pressure.

 

Another hint = Volumetric efficiency as it pertains to throttle position.

 

Also, the guy who does the car talk on usatoday.com had a thread about this a couple of weeks ago. He figured that if you drive 15,000 miles per year you might save a total of $75. He didn't recommend it or think the extra $3 or $4 per tank more it cost was worth the hit on your engine.

 

Your compression ratio does not change with throttle position or any thing else .. if the compression ratio is 11 to 1 its always 11 to 1 ... the mix of what you put in it can change, as can the temperature of what goes in but it still gets compressed at 11 to 1 at an idle or 6000 rpm at full throttle.

The throttle position controls the air coming in and tells the injectors how much to squirt related to that air ..

 

If you can afford such a great car, surely we can afford to give it what it wants and what we need from it?

 

When I open my gas door and it says "premium fuel only", I put premium fuel in it. In my opinion, why even try anything else? You could also put one less quart of oil in it when you do an oil change as well, try that? The car will still run.

To each his own... I just do what the manual and the car itself actually states.

 

From the 3G TL Garage:

C-016: 91 Octane
https://acurazine.com/forums/showthread.php?t=80062
https://acurazine.com/forums/audio-video-electronics-navigation-22/ps2-cls-89432/


C-019: Mileage and Octane
https://acurazine.com/forums/ramblings-12/just-got-back-court-104380/

Lots more with a search.

 

I wouldn't try regular under any condition - not worth the risk. The most I'd try is adding mid-grade (89 in my area). Has anyone tried mixing 93 with 89? Again as another poster stated, you buy a premium car follow directions and use premium fuel. Steve

 

regular doesn't hurt. But car does go slow. If you are grandma driver, regular will be fine

 

The difference is less than a bottle of beer at many establishments. How cheap is that!! Just put premium in. Your car will know!!

 

I put in regular once and did notice a sluggishness in the car. With midgrade I dont feel the same sluggishness. Now I tend to go between mid and premium depending on where I am when I fill up. When I go to the cheap-ass premium Costco place, I also add Techron.

 

My regular costs way more than your premium. So I'm spending hell lot of money on gas. So don't bring that equation into game.

I used regular for a while. Only problem is if you have people or cargo, you have to stay in high RPM range longer in order to keep the speed. So in that case I don't see any savings over premium. If you are only one in the car and driving not too aggressively, then you will save money with regular given you stay in lower RPM during your drive.

 

hahaha.. lol

 

I always use premium regaurdless of the price, but if i'm lucky enough to find a station that is out of regular I use mid-grade. All it is is the premium stuff but 10 cents cheaper!

 

Like dmarcus48 said, filling up a tank of premium is only about 3 bucks more than filling up with regular so you're really not saving that much money unless you fill up every few days or so. I figure if I dished out 35K on a new car that requires premium, I might as well spend the extra 3 bucks to fill it up with the recommended fuel and avoid problems in the long run.

 

I use 89 twice a week. It saves about $10 a week, and I don't feel any performance draw backs.

 

Just thought I would add my 02. While the car adjusts to low octane, remember it doesn't predict, it reacts. In other words it has to see knock before it pulls back timing to compensate. Knock is never good even in low doses. While it may not kill the motor immediately over 100,000 miles it will take it toll on rings and bearings. When you put cheap gas in and feel a surging that's the computer pulling timing. It's not worth it to use cheap gas unless of course it's a loaner lol.

The other thing is cylinder pressure is the biggest cause of pre-ignition. Throttle position and compression ratio are the biggest factors in this. Cylinder pressure and ignition timing both cause detonation. If you run cheap gas, drive it easy.

 

For my ongoing discussion with Jesstzn -

if you are at partial throttle, there is not much air to be compressed by the 11:1 compression (poor volumetric efficiency, meaning the cylinder is not filling much). Hence, lower chamber pressure than WOT.

If you are at WOT, the volumetric efficiency is near 100% and the cylinder is nearly filled-up. Now, the 11:1 compression will have a lot to squeeze which will produce high chamber pressures. High octane fuel is used to resist "exploding" when under high pressures.

 

Agreed.

The only thing I didn't quite agree with earlier in the thread is that high octane burns slower. Some burns slower and some burns faster. I run avgas in my turbo car for daily driving and it loses a little power at first compared to 91 octane until I crank the boost. On the other hand, the C-14 I used at the track actually burns faster than 91 octane and you can feel a slight power increase without touching anything. I wonder what my dynamic compression is under 28psi boost lol.

 

Agreed. Flame propagation within a combustion chamber is a complicated topic with many variables.