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So i was reading through some manuals for the SRT8 challenger and i came across this statement:

"Fuel - For optimum performance, your vehicle has been tuned and calibrated to run on Premium fuel with a minimum octane rating of 92 RON."

Can anyone here tell me where i can get pump gas with a 92 RATING? As far as i know all the gas stations i have ever been at have premium pump gas at 91 Octane..

What about adding an additive to improve gasoline octane? Anyone here doing that?

Thanks
 

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Research Octane Number (RON)

The most common type of octane rating worldwide is the Research Octane Number (RON). RON is determined by running the fuel in a test engine with a variable compression ratio under controlled conditions, and comparing the results with those for mixtures of iso-octane and n-heptane.
Motor Octane Number (MON)

There is another type of octane rating, called Motor Octane Number (MON), or the aviation lean octane rating, which is a better measure of how the fuel behaves when under load as it is done at 900 rpm instead of the 600 rpm of the RON. MON testing uses a similar test engine to that used in RON testing, but with a preheated fuel mixture, a higher engine speed, and variable ignition timing to further stress the fuel's knock resistance. Depending on the composition of the fuel, the MON of a modern gasoline will be about 8 to 10 points lower than the RON. Normally, fuel specifications require both a minimum RON and a minimum MON.
Anti-Knock Index (AKI)

In most countries, including all of those of Australia and Europe the "headline" octane rating shown on the pump is the RON, but in Canada, the United States and some other countries,[which?] the headline number is the average of the RON and the MON, called the Anti-Knock Index (AKI). It may also sometimes be called the Research Octane Number (RdON), Pump Octane Number (PON), or (R+M)/2.
Difference between RON and AKI

Because of the 8 to 10 point difference noted above, the octane rating shown in the United States is 4 to 5 points lower than the rating shown elsewhere in the world for the same fuel.
 

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not as long as you are referring to Sunoco GT II 100 (CAM II) which is unleaded. You can run any unleaded racing fuel. UNLEADED being the key word
 

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For most of the gas stations around here (GA) the Premium Gas is listed as 93 Octane. I wouldn't think FL would be that different...but who knows?
 

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After seeing hundreds of datalogs from Challengers, we recommend to run the highest octane you have available for max power.
Huh?? Octane has nothing to do with more power. That's a myth. It's an additive to prevent engine knocking -- nothing more. The common myth is that the higher octane you run, the more power you will generate, and the faster you will go. Not true. 105 octane AV gas doesn't make you go any faster than 87 octane. That's a proven fact.

The manufacturer's suggested octane for a vehicle is based upon a worse driving scenario, i.e., 100% lead foot, hilly terrain, etc. Pretty much as a rule of thumb, whatever the manufacturer suggests, run a few tank fulls of the next lesser grade octane and if you don't experience any knocking, then buy that grade instead and save yourself a bundle.

If you run higher than suggested octane, then you might want to watch your mpg. Sometimes running a higher octane can knock several miles a gallon off of your mpg as recently proven in a study with a fleet of taxi cabs.

That said, if you start making modifications, like adjusting timing, etc., a higher octane may be needed to avoid engine knock. But it's the modifications that give the car more power, not the octane.

Just saying.

For more info, see: The Low-Down on High Octane Gasoline
 

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Huh?? Octane has nothing to do with more power. That's a myth. It's an additive to prevent engine knocking -- nothing more. The common myth is that the higher octane you run, the more power you will generate, and the faster you will go. Not true. 105 octane AV gas doesn't make you go any faster than 87 octane. That's a proven fact.

The manufacturer's suggested octane for a vehicle is based upon a worse driving scenario, i.e., 100% lead foot, hilly terrain, etc. Pretty much as a rule of thumb, whatever the manufacturer suggests, run a few tank fulls of the next lesser grade octane and if you don't experience any knocking, then buy that grade instead and save yourself a bundle.

If you run higher than suggested octane, then you might want to watch your mpg. Sometimes running a higher octane can knock several miles a gallon off of your mpg as recently proven in a study with a fleet of taxi cabs.

That said, if you start making modifications, like adjusting timing, etc., a higher octane may be needed to avoid engine knock. But it's the modifications that give the car more power, not the octane.

Just saying.

For more info, see: The Low-Down on High Octane Gasoline
This is sort-of correct.

Higher octane fuel burns slower, more efficiently, more completely. The result? Improved acceleration and performance. A more complete burn results in less carbon build-up = chance of pre-detonation (knocking) down the road. HEMI engines use VVT technology, so knocking shouldn't be an issue. I prefer a clean, smooth running engine for top performance... hence, it's 93 octane for Sweet Orange. :)

The 5.7 Eagle engine runs 10.5:1 compression! Octane boosting (via ethanol) helps, but again... 93 octane. Running higher octane fuel will also extend the life of your catalytic converters.

To the OP... Octane is the anti-knock rating measurement. Pure ethanol has an index rating of 100. i.e. Octane booster.
 

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10 year old thread ;)

A Guy
 

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This is sort-of correct.

Higher octane fuel burns slower, more efficiently, more completely. The result? Improved acceleration and performance. A more complete burn results in less carbon build-up = chance of pre-detonation (knocking) down the road. HEMI engines use VVT technology, so knocking shouldn't be an issue. I prefer a clean, smooth running engine for top performance... hence, it's 93 octane for Sweet Orange. :)

The 5.7 Eagle engine runs 10.5:1 compression! Octane boosting (via ethanol) helps, but again... 93 octane. Running higher octane fuel will also extend the life of your catalytic converters.

To the OP... Octane is the anti-knock rating measurement. Pure ethanol has an index rating of 100. i.e. Octane booster.
High octane gasoline does not burn slower. It consists of blend of gasoline (iso-octane which has an octane rating of 100 and heptane). The iso-octane component has longer molecules which resist breaking down into pre ignitable compounds ahead of the advancing flame front. But once the flame front reaches the unburned molecules of gasoline they ignite and burn at the same speed as lower octane fuels.

The benefit of higher octane is because it resists detonation more timing advance can be used. If the car's engine controller can take advantage this -- using knock sensors to stay just short of detonation -- more timing advance does result in combustion starting earlier which results in more mechanical power being obtained from the fuel's chemical energy.

My experience over the years is premium gasoline while it has more detergents in it still needs some engine run time to clean the engine. In the past when I took long road trips it was common for me to head out and after a good long drive at highway speed stop and fill up the tas tank. It was driving on surface streets that I noticed the engine was running better.

The exception is when I switched from Shell V-Power to Chevron Supreme (with Techron). Just driving the car around town before the fuel tank was even to the 1/4 tank level the engine was running noticeably better.

There is no benefit in buying a grade of gasoline with more octane than the engine controller can utilize by using more timing advance. Generally if the automaker calls for say 91 going to 93 provides no benefit. However, in some cases it appears the car maker has provided the engine controller some ability to adjust to the octane of the gasoline and 93 might result in a noticeable improvement over 91.

All I can say is if you want try 93 and see for yourself.

I never had a chance to try 93 in my Hellcat. I ran 91 ethanol free and I did not notice any change for the better or worse from the Hellcat engine. The same is true of my Mercedes Benz van with a 2.0 turbo charged engine. And more recently with my 2020 Scat Pack. No improvement. Rats. But I will continue to buy it as the price is very low. $2.07/gallon. At some point I hope to try 93 in the Scat Pack and even in the van just to see if there is any benefit.

Normally running the called for octane of gasoline will provide the best chance for long and trouble free converter service life. However, if the engine controller can adapt to more octane -- and this is determined to be the case by seat of the pants dyno -- this can be beneficial to the converters. The reason is with more octane the engine controller can use more timing advance. This starts the combustion process sooner. Among the other benefits from this is more combustion takes place in the combustion chamber/cylinder. By the time the exhaust valve opens and exhaust gas flows to the ocnverter all combustion has taken place and exhaust gas temperature is lower than it it have been with a delayed start to combustion. This lower exhaust gas temperature can help extend converter life.

If it is clear that the engine "likes" 93 then more octane is good for the converters. But it the engine doesn't react favorably to 93 any benefit to the converters is unlikely.

Might mention I have driven a number of cars to 150K miles and beyond. In two cases (161K miles and 317K miles) I was not able to run 93 octane gasoline as called for in the owners manual but could only run 91. Even though I used 91 octane the converters were fine after all those miles. I have never worn out a converter.
 

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Do not insult other members
High octane gasoline does not burn slower. It consists of blend of gasoline (iso-octane which has an octane rating of 100 and heptane). The iso-octane component has longer molecules which resist breaking down into pre ignitable compounds ahead of the advancing flame front. But once the flame front reaches the unburned molecules of gasoline they ignite and burn at the same speed as lower octane fuels.

The benefit of higher octane is because it resists detonation more timing advance can be used. If the car's engine controller can take advantage this -- using knock sensors to stay just short of detonation -- more timing advance does result in combustion starting earlier which results in more mechanical power being obtained from the fuel's chemical energy.

My experience over the years is premium gasoline while it has more detergents in it still needs some engine run time to clean the engine. In the past when I took long road trips it was common for me to head out and after a good long drive at highway speed stop and fill up the tas tank. It was driving on surface streets that I noticed the engine was running better.

The exception is when I switched from Shell V-Power to Chevron Supreme (with Techron). Just driving the car around town before the fuel tank was even to the 1/4 tank level the engine was running noticeably better.

There is no benefit in buying a grade of gasoline with more octane than the engine controller can utilize by using more timing advance. Generally if the automaker calls for say 91 going to 93 provides no benefit. However, in some cases it appears the car maker has provided the engine controller some ability to adjust to the octane of the gasoline and 93 might result in a noticeable improvement over 91.

All I can say is if you want try 93 and see for yourself.

I never had a chance to try 93 in my Hellcat. I ran 91 ethanol free and I did not notice any change for the better or worse from the Hellcat engine. The same is true of my Mercedes Benz van with a 2.0 turbo charged engine. And more recently with my 2020 Scat Pack. No improvement. Rats. But I will continue to buy it as the price is very low. $2.07/gallon. At some point I hope to try 93 in the Scat Pack and even in the van just to see if there is any benefit.

Normally running the called for octane of gasoline will provide the best chance for long and trouble free converter service life. However, if the engine controller can adapt to more octane -- and this is determined to be the case by seat of the pants dyno -- this can be beneficial to the converters. The reason is with more octane the engine controller can use more timing advance. This starts the combustion process sooner. Among the other benefits from this is more combustion takes place in the combustion chamber/cylinder. By the time the exhaust valve opens and exhaust gas flows to the ocnverter all combustion has taken place and exhaust gas temperature is lower than it it have been with a delayed start to combustion. This lower exhaust gas temperature can help extend converter life.

If it is clear that the engine "likes" 93 then more octane is good for the converters. But it the engine doesn't react favorably to 93 any benefit to the converters is unlikely.

Might mention I have driven a number of cars to 150K miles and beyond. In two cases (161K miles and 317K miles) I was not able to run 93 octane gasoline as called for in the owners manual but could only run 91. Even though I used 91 octane the converters were fine after all those miles. I have never worn out a converter.
You're an idiot.
 

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You're an idiot.
My info is correct. Too bad you can't deal with that fact on an adult level.

It seems like everybody parrots that "high octane gas burns slower" BS but that is simply not the case. It burns the same speed at regular. To repeat it is blended to resist forming pre ignitable compounds in advance of the flame front. The compounds do not ignite from the heat generated by the increase in pressure and generated by the light of the burning mixture. The compound only ignites from direct contact of the flame as the front reaches the unburned molecules of gasoline.

While not the best comparison I like to say high octane gasoline is like dynamite. Hard to ignite -- in the case of dynamite it takes a small explosion (blasting cap) to set it off -- but once igntied burns with the speed that makes it useful.

Because of this resistance to forming pre ignitable compounds in ahead of the advancing flame front timing can be advanced to trigger combustion earlier which has the combustion occuring during the time the piston is in the best part of the power stroke to convert pressure created by combustion into mechanical energy. It is the reduction of this pressure by starting combustion later that keeps detonation at bay with lower octane gasoline. Pressure is reduced but power suffers as the push on the piston occurs at a less optimum time of the power stroke. Combustion is delayed which results in higher exhaust gas temperature which means all engine components exposed to exhaust gas run hotter.
 

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Warning issued, if your only argument is an insult, then please hold your tongue

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