MarkT 2002

Where do you get 93 octane? If I recall premium is 91 octane in CA.

MarkT

Matt69-ZO6

If my memory is correct, the computer in the car will not compensate for 100 octane, seems like it can adjust only to the mid 90's.

Someone can correct me, but I believe you will find no real gains or benefits - except to the retailer!

bchisom99

we've got 93 here in ohio at shell stations, thats all I use, so I'm not sure what everyone else is offering....

quickie350

For a bone stock LS6 of LS1 motor for that matter a minimum of 90 octane is suitable. Most manufacturers will say 91 to 93. Premium. Whatever you want to call it. 100 octane will not cause any damage to the motor and will probably give you an very, very small improvement in your gas mileage.
Other than that it just sounds good when you say it to someone who doesnt know.
I did have a problem in the summer with my '02 coupe pinging under hard acceleration with cheap gas, (Plus). I had the computer programmed and the variables could be modified, so I couldnt even say if the gas was the direct problem.
Now when you start getting into high compression motors the octane keeps the pre-detonation to a minimum and causes less motor damage.

barondw

I would use racing fuel only when doing a DE. Other than that IMO its a waste of money.

ylwZ06

Contrary to what many people believe, higher octane fuel does not have more energy. People have it all backwards thinking that higher octane fuel produce more power, when in reality it is a simple fact that the higher the compression a motor is, the higher the octane fuel it requires to resist detonation.

If you have a non computer controlled car running a given octane and you have knock, then running a higher octane fuel will indeed produce more power, because of the fact that the knock is eliminated, or if you run higher octane fuel, you can then manually advance and run the timing higher, therefore producing more power. If you are runnig a computer controlled car, and if it was tuned from the factory to run 100 octane fuel and you ran say 92 octane, then it would probably knock and therefore the knock sensors would send a signal to the ecm thus retarding the timing to eliminate knock and therefore reduce the horespower output of your motor. However, since our Z's are tuned for 91 octane, there is no way the aforementioned would hold true.

If one does not believe my statements, go run dyno tests, go run track time tests, give concrete data, but I guarantee the data would not substantiate the "assometer" claim.

Vettez16

I run 93 Mobile or Amoco, Since the new performance tune demands higher octane I now run Sunoco 94. I will say this, the car was already a rocket so the tune only helped. My 78 vette on the other hand, probably due to age, simply will protest anything less than 93. octane. Once an attendant by accident put in 87 octane and I might as well have been driving a Model T, ping city. My Point is 90 or 91 should be good enough as I believe the engine was factory tuned for this rating and the compression more than adequate.

slamar1

Your car is set for premium (91-94). No need to spend the money

MD Petite

Sorry I just didnt know sorry for as one of you put it the assometer
question!!!!!!!!

Lancer033

assuming that you don't change anything in the engine, you can also run lower quality fuel during cold weather and at higher altitudes w/o detonation. during the summer, my car ran like crap when I filled it up on base, so I started buying gas off base and everything cleared up, but when winter hit I started filling up on base again and haven't been any problems. In short, run the lowest octane that won't cause your engine to knock any more than that is a waste of money. the LS1/2/6 are good with anything above 91 octane.

incase anyone in Europe reads this, 98 octane here is the same as 93 in the states.

LTC Z06

Not only will it not burn anything but the higher octane, slower burning fuel is actually a little cooler because it does burn slow. The old myth about higher octane burning things comes from the days when we left leaded gas behind, and people were burning valves.

soblad

Please run some answer's on my Question (see my new thread 2002 Z06) this one will blow you away.

Sid

FRISKY

Higher octane fuel usually burns faster.

Like others posting in this thread have said; you typically will not gain any advantage by running higher than 93-octane on a stock engine.

Cap'n Pete

Maybe once it's ignited. However, higher octane fuel needs a lot more heat to burn than low octane fuel (this heat comes from higher compression) so given a fixed compression, and low or high octane fuel, the low octane fuel will ignite faster. Will the higher octane actually burn faster once it's ignited? I guess???

l2vette

Fuel the Beast!!

Mallory

No it doesn't... It burns slower... Ping is PRE-Detination. So the fuel is burning too early. By extending the burn time, it will create presure over a longer time instead of popping everthing at once and being done.

On the origional question.. If your car does not ping the higher octane does nothing for you.

Eric

WALLstAL

Certain Union 76 station sell 100 Octane race fuel. They usually keep it in the back in drumbs.

WALLstAL

Certain Union 76 station sell 100 Octane race fuel. They usually keep it in the back in drums, cost about $6 a gallon.

FRISKY

Sorry, that is not correct. You are confusing "burn rate" with "ignition rate", two entirely different issues.

“Burn rate” is how fast or slow the fuel will complete combustion once it has been ignited. Typically this process will be completed within 20-degrees of crankshaft rotation from TDC, and that is a very small amount of downward motion of the piston in the bore.

“Ignition rate” is how quickly the fuel can be ignited and is a product of octane. The higher the octane number, the more heat and pressure will need to be generated in the combustion chamber before the fuel can ignite.

Chemicals added to gasoline to increase the resistance to pre-ignition/spark knock/detonation also decrease the amount of BTUs available per pound of fuel. That is why you should use the lowest octane fuel possible that won’t cause the computer to pull timing or “pinging”.

Popular Hot Rodding Magazine, January 1998
By Scott Parkhurst

"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 higher octane ratings and faster burn rates.

To give you a good example of this, we contacted Jim Wurth from Sunoco Race Fuels. He 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 9,000 rpm or more, the fuel has to burn pretty quickly to achieve complete combustion".

FRISKY

If you chose to try some of the 101-octane fuel, make sure it is unleaded. Using leaded racing fuel or Aviation gas will cause problems with your catalytic converters and oxygen sensors.