It is great, especially if you have a revup motor and a tuned map for it. If I remember correctly, it was something like a 15 hp gain. Even still, I stuck with 91 for daily driving due to the high cost of 100. But without the tune, it's just expensive for small gains and benefits. If you track your car, then get 100 for track days. It's not worth the money for daily driving.

 

apparently not enough to run 100 octane! lol
Custom Catback exhaust (I love the sound). Im gonna post a video tonight I think.
K&N typhoon.
UPREV. Thats it for performance mods.

 

100LL is actually a good detergent fuel.

every now and then i run 5 gallons and top off with premium fuel. it helps eliminate carbon build up.

The cons:

with a stock ecu you are doing NOTHING for power output. Will the car run safer yes. But safer from what? You have to remember the ECU's are programmed for fuels readily available to the public and to ensure that the engines run safely under normal operating conditions.

The car will run safer as it will help prevent pinging. But no matter what, if you cannot control the tune of the ecu your money is just going down the pipes.

to continue the onslaught of the cons, the LL on 100LL stands for Low Lead. Although it has a low parts per million lead count it still contains lead. for a car with Oxygen sensors and catalytic converters this is very important. Lead is a danger to cats and the o2 sensors as it prematurely damages them.

Bottom line:

Will the car gain performance out of the box with no tuning and just 100octane (NO)

Will the car run safer, yes and no. If you have straight pipes and no o2 sensors yes... OEM equipment NO.