Octane Booster

[alkeshtech]

Hey Guys,
I was just reading few articles on improving MPG. They mentioned adding an octane booster into the gas tank. Has anyone had an experience with it? Does it really help engine run smoother and thus helping MPG? Is it worth it on camry'09 SE. If so, which brand should I buy?

Thanks.

[GT-R]

If I were you, just leave the car alone, fill it up with regular gas, and call it a day.

[ohhey]

Originally Posted by alkeshtech

Hey Guys,
I was just reading few articles on improving MPG. They mentioned adding an octane booster into the gas tank. Has anyone had an experience with it? Does it really help engine run smoother and thus helping MPG? Is it worth it on camry'09 SE. If so, which brand should I buy?

Thanks.

As octane goes up gas does not burn as well and the car will use more of it. You don't need that in a Camry, it's not a high compression system. High octane is good for cars with high compression engines because it prevents that pinging sound but it still uses more gas. Works just the opposite then most people think it does.

As a rule it's best not to add anything to your gas.

[TRD VVTi]

Originally Posted by ohhey

As octane goes up gas does not burn as well and the car will use more of it. You don't need that in a Camry, it's not a high compression system. High octane is good for cars with high compression engines because it prevents that pinging sound but it still uses more gas. Works just the opposite then most people think it does.

As a rule it's best not to add anything to your gas.

Actually, the Camry does have a high compression engine.

Octane booster will not increase your fuel mileage.

[catric69]

Just before every oil change I dump seafoam in the crankcase. Also, some in the gas tank before I fill up. I haven't bothered with octance booster in years.

[ohhey]

Originally Posted by TRD VVTi

Actually, the Camry does have a high compression engine.

Octane booster will not increase your fuel mileage.

Good luck with that..

[TRD VVTi]

Originally Posted by ohhey

Good luck with that..

None needed. Facts have nothing to do with luck.

[BlackCamSe]

No, it wont increase your mileage. Plus even if it did, its about 2-5 dollars a bottle. So the cost would outweigh the extra 1 or 2 MPG

[alkeshtech]

thanks for helping guys.

[RoseMobile]

Originally Posted by ohhey

As a rule it's best not to add anything to your gas.

I normally put a bottle of lucas fuel injector once a month

[ben805]

octane booster = stay away! try one bottle and pull your plugs after you're done with that tank....you'll see what i mean.

[geoff5093]

Originally Posted by RoseMobile

I normally put a bottle of lucas fuel injector once a month

Same here, I try to do it with every oil change.

[ben805]

Originally Posted by geoff5093

Same here, I try to do it with every oil change.

I prefer the 44K fuel system cleaner, use it every 30K miles. Usually toyota, GM and other dealers sell them as well.

[rule62]

In many high-performance situations, riders clamor for higher octane fuels, thinking this will give them additional horsepower and, thus, an advantage over the competition. But this is not the case--adding higher-octane race fuel to your car may actually produce less horsepower. Here's why: Octane, an arbitrary number which is calculated as the average of the Research Octane Number (RON) and the Motor Octane Number (MON), and is only an indication of a fuel's sensitivity to knock, which is typically pressure-induced self-ignition. (Of these two ratings, MON is more applicable to racing fuels as it is measured under high load and high speed conditions.)

Octane, as you can see, is not a measure of how much power--or, more correctly, specific energy--is contained in a fuel. And remember that leaded high-octane race fuels burn slower than most unleaded fuels, and may reduce performance in stock or lightly modified cars. A high octane rating itself, however, does not mean that the fuel is slow burning. Hence, it has no direct bearing on the power characteristics of the fuel.

The knock tendency (and hence, the Octane rating) of a fuel is a function of the amount of free radicals present in the fuel prior to ignition and can be reduced by the addition of tetra ethyl lead, aromatics and other additives.

Although some racing organizations still use maximum octane number as the discriminating factor for fuel legality, it is really not appropriate for racing purposes.

Instead one should look at the amount of energy (heat) released in the burning of a particular fuel. This is described by the specific energy of the fuel. This quantity describes the amount of power one can obtain from the fuel much more accurately. The specific energy of the fuel is the product of the lower heating value (LHV) of the fuel and molecular weight of air (MW) divided by the air-fuel ratio (AF):
Specific Energy = LHV*MW/AF

For example, for gasoline LHV= 43 MJ/kg and AF=14.6, while for methanol LHV= 21.1MJ/kg (less "heat" than gasoline) and AF=6.46 (much richer jetting than gasoline). Using the above formula we see that methanol only has a 10% higher specific energy than gasoline! This means that the power increase obtained by running methanol, with no other changes except jetting, is only 10%. Comparing the specific energy of racing and premium pump gas you can see that there is not much, if any, difference. Only alcohols (such as methanol or ethanol) have a slightly higher specific energy than racing or pump gas.

Other oxygen-bearing fuels, besides the alcohols and nitromethanes, such as the new ELF fuel, will also produce slightly more power once the car is rejetted. However, at $15.00 to $20.00 at gallon for the fuel the reportedly minor (1% - 2%) improvement is hardly worth the cost for the average racer.

The real advantage of racing gasolines comes from the fact that they will tolerate higher compression ratios (due to their higher octane rating) and thus indirectly will produce more power since you can now build an engine with a higher compression ratio. Also, alcohols burn cooler than gasoline, meaning even higher compression ratios are possible with them, for even more power.

The bottom line here is that, in a given engine, a fuel that doesn't knock will produce the same power as most expensive racing gasolines.

However, it sometimes happens that when you use another fuel, the engine suddenly seems to run better. The reasons for this are indirect: First, the jetting may be more closely matched to the new fuel. Secondly, the new fuel may improve the volumetric efficiency (that is, the "breathing") of the motor. This happens as follows: Basically a fuel that quickly evaporates upon contact with the hot cylinder wall and piston crown will create additional pressure inside the cylinder, which will reduce the amount of fresh air/fuel mix taken in. This important--but often overlooked--factor is described by the amount of heat required to vaporize the fuel, described by the 'enthalpy of vaporization' (H), or 'heat of vaporization' of the fuel.

A high value of H will improve engine breathing, but the catch is that it leads to a different operating temperature within the engine. This is most important with two-strokes, which rely on the incoming fuel/air mix to do much of the cooling--even modern water-cooled two-strokes rely on incoming charge to cool the piston. For two-strokes a fuel that vaporizes, drawing a maximum amount of heat from the engine, is essential--the small variations in horsepower produced by different fuels are only of secondary concern.

Also important is the flame speed: Power is maximized the faster the fuel burns because the combustion pressure rises more quickly and can do more useful work on the piston. Flame speed is typically between 35 and 50 cm/sec. This is rather low compared to the speed of sound, at which pressure waves travel, or even the average piston speed. It is important to note that the flame propagation is greatly enhanced by turbulence (as in a motor with a squish band combustion chamber).

The most amazing thing about all this is that you can get the relevant information from most racing gasoline manufacturers. Then, just look at the specification sheet to see what fuel suits you best: Hot running motors and 2-strokes should use fuels wit h a value of "H" that improves their cooling, while more power (and more heat) is obtained from fuels with a high specific energy.

By the way, pump gas has specific energies which are no better or worse than most racing gasolines. The power obtained from pump gas is therefore often identical to that of racing fuels, and the only reason to run racing fuels would be detonation problems, or, since racing fuels are often more consistent than pump gas--which racers call "chemical soup"--a consistent reading of the spark plugs and exhaust pipe.