Will high octane really damage my engine?

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LOL, you really are funny Miles. There was nothing rambling about it, you either just can't understand it or you are just not man enough to admit to possibly being wrong. I believe that it is a lot of both. LOL, and I thought that I was bad. Please prove even one of my points wrong, oh, that's right, you can't and yet, you still insist on me being wrong. Sorry Miles, but until you do, you are just being a whining crybaby that just likes to argue with nothing to back it up.
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TBone wrote:

TBOne, look at that crap you just wrote! If that ain't a pure sad lonely troll! Geez, some ppl's kids. Crap doesn't need to be proven wrong! Now be silent!
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Yawn. Like I said, no real knowledge, just wanting to argue.

Now that would be you with your childish arguments that you are unable to back up.

While true, you are even unable to prove what I said was crap although with your proven lack of knowledge in this area, I can see why not.

Perhaps you should follow your own advice Miles and learn a little something about vehicles before jumping in and proving your ignorance on the subject. As for me, since you are completely unable to make any point at all, I'm done with this.
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TBone wrote:

lol, another several paragraphs of drabble out of you...and yet you're done with this? lol. Too funny but I hope you keep your word.
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wrote:

You are ASSuming that burn rate and octane rating are related. also ASuming higher octane fuel burns slower. This ASumption is not necessarily true. The burn rate of a fuel is a measurement of the time required for complete combustion of the air/fuel mixture. The notion that octane ratings affect the burn rate of fuel is about 180-degrees from reality. Burn rate is a function of several variables, and the two are completely independent. Although there is generally a correlation between octane ratings and burn rates, the fuel mixture ratio has a lot more effect on burn rate than octane rating does.
To give you a good example of this, Jim Wurth from Sunoco Race Fuels. explains, "A perfect example is Sunoco Maximal, which is our fastest burning fuel, and coincidentally one of Sunoco’s highest octane fuels at 116 (R+M)/2. A lot of Pro Stock teams rely on Maximal for those sub-seven second runs. When they are turning 9,000rpm or more, the fuel has to burn pretty quickly to achieve complete combustion."
However he also says AVIATION high octane fuel has a significantly lower burn rate, being designed to run in engines running at 3000RPM and less. It is not a good idea to run AvGas in a car. BUT - add a small amount of leaded AvGas to unleaded MoGas, and the octane increases significantly more than the mathemathical ratio would suggest, without slowing the burn rate appreciably.
One reason some people think octane and burn rate are related is because some (most) high octane fuels are lower in Specific Gravity (below 0.75)than regular unleaded (generally 0.75 or higher), which causes the engine to actually run leaner. Burn rate of a lean mixture is slower than burn rate of a rich mixture.
This is not uneducated conjecture - it is from fuel company experts.
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But it is not false either and I am not the one saying high octane fuel will cause damage to certian engines, the MANUFACTURER is!!! I am simply giving a possible reason as to why.

Really, how? Octane is a level of fuel stability and it is impossible to make a given fuel more stable without affecting the burn rate.

Hahahaha, talk about doubletalk. While as you say, many variables that can effect the burn rate, there cannot be a correlation between octane ratings and burn rate unless octane ratings effect the burn rate as well, regardless of the effect the mixture or other variables may also have on it.

Do you really think that you can put this in your car and it will run ok????? You are also comparing apples to airplanes. This is a racing fuel refined for specific needs that are very different than that of automotive fuel. If you dropped the octane rating of this specific fuel, it would burn even faster but at a cost of significant instability that is simply not worth the small increase in speed.

It would not be a good idea to put either one of these fuels in a modern fuel injected vehicle. Either one would make the vehicle run like shit because the computer is not set up for the characteristics of either one of these fuels.

But here is the key word, appreciably. IOW, it WILL slow down the burn rate, just not by a huge amount. The problem is that it doesn't have to be slowed down by a huge amount for a computerized emissions specific computer to react to it.

You really need to stop talking out of both sides of your mouth. For any SPECIFIC FUEL TYPE, a change in octane reflects a change in the burn rate. Comparing different fuel formulations and types is like comparing apples to grapes, regardless of the octane ratings. When you can provide proof that for a specific fuel, changes in the octane ratings have no effect AT ALL on the burn rate, then you win and perhaps you can then inform the manufacturers of the vehicles that they are wrong and should remove their bogus warnings as well but until then...

Ok, I'm not going to argue this or the reasons for it but lets put your claim to work. For a specific fuel type and or make, an increased octane rating indicates a slower burn rate and nothing that you have said so far says anything different. If the computer in the vehicles with this warning are configured based on the burn rate of REGULAR unleaded with tight emission tolerances, the slightly slower burn rate of super will cause the computer to see a rich condition. Since these computers are configured to control emissions over performance, it will probably cut back the injector pulse width to lean out the mixture. Now according to you, that will slow the burn rate down even further and may make the computer think that the problem has not improved enough for the current reduction or may have gotten worse. Either way , now it will further lean out the mixture and / or increase the timing until the O2 sensor indicates that the emissions are within specifications. Lean mixtures burn hotter and are far more unstable and likely to ping than the correct mixture and combined with advanced timing.... You really need to look at the complete picture. The computer controls the mixture depending on what it sees on the emission side and if it thinks it is delivering too much fuel based on excess unburned fuel entering the exhaust, it will cut it back, possibly to the point of causing damage over time.
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I see you are up to your usual bullshit. You obviously don't understand what octane does for a fuel. Shut up now.
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Hey Max. what's up. Talk about PKB, now GFY
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"Max Dodge" < snipped-for-privacy@verizon.net> wrote in message
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Oooh, acronym soup. Yer so fulla shit, its spewing out yer mouth. You ought to try opening your asshole as much as you open your mouth, then that stuff would go out the right way.
SSDD with you, the ultimate PITA.
Wow, I can do that too.
Your turn!
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Max

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wrote:

T-Bone - I'm not going to get into an arguement here - but the fact is that the burn rate varies more from manufacturer to manufacturer, within the same "grade" of gasoline, than it does from regular to hi-test in a particular brand. There are MANY ways to change the octane rating of fuel - some of which will have more effect on burn rate than others. I do not think the burn rate has as much effect on the emissions systems of todays cars as you think it does. First of all, the O2 sensor, which is the ONLY part of the system that monitors the mixture, has no idea how much fuel was unburned - only the amount of oxygen in the exhaust. Granted - this IS a pretty good indicator of how well the fuel is being burned - but by the time the slow burning fuel in your description hits the O2 sensor it has more or less completed it's burn, whether it has converted its heat energy into torque (cyl pressure) or not. If the fuel has not completed it's burn, the O2 sensor will sense excess oxygen, which it will interpret as a LEAN mixture - not rich - and it will RICHEN the mixture to compensate. Since the mixture strength has significantly more effect on burn time than octane change does, the burn time will speed up with the richened mixture, compensating and bringing the oxygen level in the exhaust back down to within range. If the O2 level in the exhaust drops too far, the engine compensates by leaning the engine - which causes the burn rate to slow down, restarting the cycle. This can happen at close to 8000 times a minute on a 4 cyl engine at 4000 RPM - or 12000 times a minute at 6000 RPM. Add to this the fact that MOST engines now have knock sensors, with adaptive ignition timing. The engine runs as advanced as possible at all times. This means the burn time is less critical than if the engine was running later ignition timing. Timing is only retarded when the knock count reaches a given (programmed) knock threshold. This knock threshold is reached earlier with low octane fuel than with premium.
All of this is NOT to say that some of today's engines MAY not have an adverse reaction to high-test fuels - but that if they do it is for a different reason. A POSSIBLE reason is that IF the burn rate is too slow, and IF that causes the O2 sensor to tell the computer it is running too lean, and IF the computer overcompensates, causing the engine to actually run richer - and IF this causes the engine to carbon up, THIS could contribute to engine knock/detonation by both raising compression ratio and causing hot spots in the cyl (glowing carbon).
We KNOW that certain vehicles built in the last 15 years have a carbon deposit problem under certain conditions, and that this causes detonation problems on these vehicles. Dodge Colts and Toyota Tercels are two examples of these vehicles. Whether fuel octane ratings contribute to this problem or not is strictly a matter of conjecture at this time - but my FEELING is it does not - as the problem exists on vehicles run exclusively on regular fuel - I can't say if it happens as often or as severely as on vehicles run on hi-test - so this is not the ONLY explanation, if indeed it is valid at all. I'm not saying I totally understand the entire combustion process - but as you may remember I have taught the trade in the past, and have a little bit more than a passing aquaintance with engines and engine control systems and theory. There are a LOT of theories out there - many of which do not stand up to close scrutiny. What we DO know is the manufacturers will "cover their behinds" in as many ways as possible when it comes to legal mumbo-jumbo, and if there is any possibility that CAFE and or emissions standards MAY be compromized by use of a given (not manufacturer supplied) product, they WILL warn against it's use. But will they fix "known" mechanical or safety problems if the accountants think they can play the odds and buy off the "victims" cheaper than fixing the problem???? We all know the answer to that one too.
Just some more to think about. Have a good weekend.
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Excellent response, thank you. It appears that I got my fuel burn rates regarding rich / lean mixtures completely backwards, oh well. Now it looks to me like those warnings could be to prevent a possible rich run condition that would cause premature converter failures that the companies would have to pay for. You have a good weekend as well and thanks again.
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We'll await the apologies you owe for calling people names and being rude when you were in fact, wrong. Probably won't happen, oh well.
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LOL, nice try Max but the truth is that you didn't say anything of value in your previous post and as usual trying to take credit for someone else's knowledge. BTW, who is the we you are talking about? Go back to your corner troll boy.
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"Max Dodge" < snipped-for-privacy@verizon.net> wrote in message
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TBone wrote:

Nice try at avoiding an apology TBone. You ranted all over against me saying I didn't know how engines worked. Who gives a rats ass about credit. Is that what this is all about to you? Fact is, you were wrong and are not big enough to apologize for your long winded rants.
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What is it exactly that I'm supposed to apologize for Miles?
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"miles" < snipped-for-privacy@noemail.com> wrote in message
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TBone wrote:

lol. Figures! Rant away then claim you're clueless.
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Thats correct, to a point. While I didn't contribute to the subject, I did tell you to shut up. Thats got plenty of value in several peoples view, I'd bet on it.

Rubbish. I did nothing of the sort. I told you that you didn't understand octane, and the guy with the knowledge proved exactly what I said, you hadn't a clue.

I bet Miles at the very least is part of the "we" that deserves an apology for the crap you spew.

LOL, speaking of PKB....
Your turn!!
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Suddenly, without warning, snipped-for-privacy@sny.der.on.ca exclaimed (12-Jun-05 2:30 AM):

Ok, now I'm getting a bit lost. In your opinion, if I use "Premium" high octane (95) fuel (whatever formulation they use here in the UK) will there be damage my engine, whether it runs rich, lean, or within specs?
jmc
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On Sun, 12 Jun 2005 21:22:47 +0100, jmc

run richer, driving it a bit harder (which most premium users will do by instinct)will help chase out any carbon build-up. If it runs lean, unless you are chasing it's tail very hard, you will not have an overheating problem - you may have driveability problems - but I doubt it. If it runs within specs, no problem.
You MIGHT end up with a damaged catalitic converter, but whether that would hapen significantly sooner than normal is rather doubtful.
Just my (somewhat educated) opinion on the subject.
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Suddenly, without warning, snipped-for-privacy@sny.der.on.ca exclaimed (11-Jun-05 9:20 PM):

Ok, so assuming this is true, how would I figure out if this particular fuel is safe?
jmc
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