Octane question

[CrazyCalvinWilliams]

I don't have a Firebird yet but I will be buying one soon, so this is a theoretical.

There is a boat launch near me that sells 110-octane and 112-octane ethanol free unleaded gasoline. Can I run this in a 2002 WS6?

[Too Fast]

Yes you can use it, but you won't benefit from the octane unless your engine is tuned for it.

You will possibly notice a very small boost in MPG, since it isn't diluted with ethanol. E85 has roughly 70% of the energy content of standard unleaded, so E10 (which is about the standard ethanol content of a lot of gas in the US now) shows a slight drop in MPG, maybe 3%, VS. straight gas like at the boat launch. How much does this gas cost?

Now for boosted cars, E85 can be beneficial since the octane of E85 is in the high 90s, it isn't actually 100-105 like usually talked about.

[35th-ANV-SS]

I would not recommend using anything other than what the motor calls for; 91-93 octane unleaded fuel.

[SMWS6TA]

^^ besides all that you'll need to make timing adjustments and correct plug for the higher octane. Can stock pistons handle the higher combustion?

Make sure it's unleaded fuel. Some 110 octane fuels still have lead in them, it will kill your O2's and Cats (if you still have them).

Also compression ration matters. Most stock cars run 9.1 to 11.1. Race gas (110 Octane) prefers 11.5 and up. Higher the compression the better the results. The more Octane in the fuel the cooler and slower the burn is.

Here's an article that can express this all better.


Can I Run Race Gas In My Street Car?

[SMWS6TA]

I'm not saying you can't run it, just that you need to make sure your that your motor can do it and not grenade it. Tuning is a big part of it, just like with Nitrous.

[OKSS]

A high octane number will not hurt anything. You will gain nothing from it without higher compression and timing advances.

As long as it is UNLEADED and NON-oxygenated, you will not hurt anything but your wallet.

For what it's worth, more than likely since it's at a boat dock it is standard Sunoco 110 which is a LEADED, NON-oxy fuel that is commonly used for the marine motors that do not use 02 sensors, cat. converters, etc. Make double sure you find out exactly what it is before putting it in your car. While lead is an effective octane booster, it will have detrimental effects on emissions equipment. Just my .02.

[pajeff02]

Your engine performance may actually suffer slightly when you feed it a super high octane fuel without making the appropriate adjustments to your tune. As posted, better to stick with something in the 91 to 93 octane range.

[Whamhammer]

I remember some guy in my neighborhood buying aviation fuel for his 81 Camaro because "it had lots of octane", the thing revved like crap.

I wouldnt put a fuel that was 15-20 octane points more than the factory insisted, without being tuned for it.

[OKSS]

I remember some guy in my neighborhood buying aviation fuel for his 81 Camaro because "it had lots of octane", the thing revved like crap.

I wouldnt put a fuel that was 15-20 octane points more than the factory insisted, without being tuned for it.

Aviation fuel or "AvGas" is a LEADED fuel normally around 100 octane. It has a high specific gravity and is made for high altitude/low RPM engines.

Although the fuel does EXCEPTIONALLY well and rivals the performance of E85 in 2 stroke motors.

[SMWS6TA]

^^also AVGAS is different then JET fuel.