He he! I use the stuff as plastic model cement!

 

Again, If you're not running a huge turbo, WHY WOULD YOU WANT SUCH A HIGH OCTANE RATING!!???

If your engine is not detonating you are running plenty of octane, the higher you go the more carbon buildup you are going to have.

Changing the octane rating of your fuel DOES NOT INCREASE POWER. It allows more power because you can change other factors, ie, advanced ignition, raised boost (not an issue for you guys).

And I think that toluene is the cheapest way to drasticly raise octane ratings, but only if you buy it in a 55 gallon drum. Which you have to show ID for and fill out some stuff, Where you are taking it, where it will be held, etc. Because it is also used for making some kind of contraband.

 

...and again:

...it'll make a difference in power, whether the engine needs the octane difference or not (which is why racers don't go around using kerosene or any other low-energy high octane fuel)

 

Well said - again! :D

Cheers,
Hymee.

PS - I hope "Miatas" is not some kind of yeast infection or something. Oh - those kind of Miatas. We call them MX-5's. Hehehe. 'On-ya mate! I can just see your add in the "personal column"... Interested in meeting gorgeous females with an keen interest in cars (bla bla bla).... Must include photo of your Miata Hehehe

 

Racer's need higher octane because they run mad amounts of compression.

Higher octane fuel doesn't actually give more power, if you are all so sure it does make more power;

show me the dyno sheets.



:D Then again, I guess you rx8 guys don't really like seeing dyno graphs on your cars.

 

That should be "Higher octane fuel doesn't necessarily give more power". For the same energy content fuel, that is true - a gasoline of high octane doesn't give more power than gasoline of low octane.

Octane rating and energy content are not related - as has been said several times in this thread, you can have a high octane fuel like kerosene, very resistant to detonation, that doesn't have as much energy content as gasoline - therefore, it makes less power.

If you choose a fuel that is knock resistant (ie high octane) with a greater energy content than gasoline (like toluene), then of course it gives more power than gasoline.

You need to understand the difference between energy content and octane.

Regards,
Gordon

 

Agreed - 100% It increased the thermal efficiency of the engine.

Well - that all depends what you use to increase the octane rating. If you use Toluene/Zylene, you are using a chemical that will give more power and more anti-knock. If you use propane/butane (or some other ****) you increase the anti-knock (octane), but don't get much bang (power).

The correct statement is "An increase in Octane does not necessarily give a boost in power, but it might, depending on many factors, such as engine design, fuel design etc."

Cheers,
Hymee.

 

Good post - you beat me to it. So many people just don't understand this! The funny thing is - it is all here...

Cheers,
Hymee

 

Alright, it doesn't necessarily make more power. I understand the difference, but with an unmodified engine how are you going to take advantage of that possible gain in energy (which more than likley will just be released as added heat).


Like I said, show me the dyno.

 

what makes you think that the thermal efficiency of the engine changes with the amount of chemical energy in a substance???? it doesn't. a very very similar proportion of the energy will be transfered to the wheels, and given that it's a considerably higher "concentration" of power, you will end up with more power at the wheels for any given amount of fuel.

of course it makes more power, just as running propane in the same engine would make considerably less power.

 

uh, okay, so a chemical has more 'energy' and that energy automatically becomes more horsepower and torque. NO.

You are saying all that extra energy goes to the wheels?

Have you ever seen a breakdown of where the power from fuel in an engine goes, most of it is heat, out the exhaust, through the waterjackets and through the metal. So, while you may be able to extract a small amout of additional power (maybe... I haven't seen the dyno graphs) you are adding alot of heat. It's a good thing that these chemicals resist detonation, because heat like to cause detonation.

MORE ENERGY=MORE HEAT

You can't just add a chemical with more 'energy' and not get more heat. Plain and simple.

 

Bigger "bang" = more effective pressure on the piston/rotor = more force = more torque = more power, and some more heat. The reverse of your argument says we can continue to "weaken" the energy value of the fuel, maintaining the same power output, and the engine just gets colder. At some point we have an engine running at room temp, putting out the same power as before. D'oh. Yes some energy is lost - we know internal combustion engines have low efficiency, but it is a %... If we have 70% losses to start with, and we also have 70% losses with a "better" fuel, but the fuel has 3% more energy, we would still get 3% more useable power, as well as 3% more energy wasted in heat etc. Nobody said all the energy would go straight to the wheels.

Cheers,
Hymee.

 

take alcohol for example, plenty of engines run off that. And nitrous oxide.

 

He didn't say that - he said the same proportion of the additional energy would end up as power, and also that the same proportion of energy would end up as heat. yes, more energy = more heat. More energy also must = more power.

Say your average piston engine or rotary engine is 30% efficient at turning energy into power, and 70% of the energy goes to friction and heat losses. So if you have fuel with energy of 100 units, then that engine converts it to 30 units of power and 70 units of heat. If you have fuel with energy of 120 units, then that engine MUST convert it to 36 units of energy, and 84 units of heat. Same ratio. More energy = more power and more heat.

Plain and simple thermodynamics and machine efficiency. Your assertation that the extra energy "more than likley will just be released as added heat" doesn't stand up to the most basic scientific analysis.

Regards,
Gordon

 

thanks Gord... sheesh.

 

Then do it to your engine, put it on a dyno, and prove me wrong

 

If you actually looked up the energy content of the fuels you're debating instead of just guessing, you'd find that alcohol has lower energy content than gasoline. That's why alcohol-fueled vehicles get poorer mileage than gasoline vehicles - they need a larger quantity of fuel to do the same work (energy).

Nitrous oxide isn't a fuel at all - it's a source of oxygen. Any automobile using nitrous has to inject additional gasoline to provide the energy.

Regards,
Gordon

 

and nitrogen that cools.

 

Bottom line, all this arguing about what fuels 'probably do' is ridiculous, when you show me some dyno sheets I'll be convinced.

 

One reason they run alcohol so they can get hight termal efficiency from having higher compression (like you mentioned). It has a higher anti-knock rating, but I don't know about it's calorific value (energy / volume).

Nitrous is not used as a fuel, but as an oxidizing agent, and it also cools the incoming charge (heaps) to make it more dense, equalse more molecules to burn = more energy.

Man, your dragging this thread down.

 

I have - in my mechanical engineering courses at university, we spent one whole course analysing internal combustion engines of various types - piston, rotary, turbine, gas, diesel. There's plenty of data that proves this info - even look at the ratings for dual fuel vehicles, like Ford's Taurus alcohol/gasoline test vehicles.

It looks like you're the one who needs to do the basic research - my Mechanical Engineering degree is already testament to the fact that I know what I'm talking about. You apparently don't know what you're talking about, since you obviously lack the basic understanding of thermodynamics and engine efficiencies.

Regards,
Gordon

 

sorry for draggin down the thread, I believe that toluene is great, I run it in my engine, but I have this thing, it's uh, what do you call it,

oh ya...... boost.

 

Nitrogen is a friggin inert gas - it doesn't combust, and thus offers absolutely no energy to the process! It's just a convenient carrier for the oxygen molecules.

The fact that nitrous oxide cools has nothing to do with it being nitrogen, and everything to do with the expansion of the gas from under pressure to atmosphere. It also has nothing to do with the discussion of the relative energy content of toluene vs. gasoline, which is the discussion that you're losing badly.

Regards,
Gordon

 

On-ya Gordy. It is as if our minds are one. That is twice now we have said the same things in different words, posted at the same time...

I don't need to give a dyno reading. My car has a shitload of water in the fuel. The Octane rating was really high (aka anti-knock rating), but it did not run. I did not nead a dyno to tell me that. Like wakeetch said - Sheesh. If it simple f'ken common sense. And a bit of the laws of thermodynamics.

Cheers,
Hymee.

 

ROFL!!!

Amen to that!