Octane 110

[bigdaddyD]

Just a quick question, can octane 110 damage a stock alero? i know its racing gas but wasnt sure if it would cause damage to the engine?

[doubleN0alero]

As far as I thought it would cause the engine to burn at too high of a tempature damaging your internals.

[[ion] C2]

Most 110 octane fuel is leaded. Bad.

Unleaded 100+ octane will not increase any performance on a stock Alero. It increases the resistance to spontaneously combust. I use 93 octance since the increased cylinder pressures would cause detonation if I used 87 octane, the higher the octane, the higher the resistance to burn.

It's funny how most think higher octane means higher combustion temperature and that it's a lot more flammable. Not true.

http://en.wikipedia.org/wiki/Octane_rating

It should be noted that octane rating does not relate to the energy content of the fuel (see heating value), nor the speed at which the flame initiated by the spark plug propagates across the cylinder. It is only a measure of the fuel's resistance to autoignition.

Higher octane ratings correlate to higher activation energies. Activation energy is the amount of energy necessary to start a chemical reaction. Since higher octane fuels have higher activation energies, it is less likely that a given compression will cause knocking.

[Redog]

I ran one gallon of 100 in the Alero once. I was at the track and very low on fuel and the closest gas station was over 5 miles away.

Anway I bought a gallon to get me there, 100 was the lowest they had. The car ran at a very high RPM, even after putting in a full tank of 93. It ran bad for about a week and the RPMs at 70 were about 2800 compared to just over 2000.

My mech said I'm lucky I didn't burn a valve

[bigdaddyD]

sounds like its a bad idea then, ok, ill stay away from the 100+ and just stick to the 91, although with gas spiking lately i might drop back down to 83.

[alerored04]

91 wont do any good unless you are tuned for it. Stick to 89 or 87.

[BlackJack]

The factory tuning in an Alero is designed to operate at peak efficiency with minimum octane ratings. If you'll notice, your performance and efficiency actually decreases when you jump from 87 to 91.

Reason for this: Higher octane fuels (above 91) need significant retuning to ensure proper quantity for proper burn (A/F). You're actually creating a lean condition which as previously stated could burn a valve.

Some of the key reasons to increase octane are:

1) Increased compression - reduces chance of detonation
2) Ability to advance the timing more - reduces chance of detonation

Neither case would apply in your situation.