Jim Will

went to the local track and got 3/4 tank of 100 octane Sunoco unleaded.
The tank was just under 1/4 tank, so I put $30 worth in the tank. There were other guys there with late model cars (one in particular a single turbo supra) loading up with the 112 octane leaded, and these cars were running a street exhaust (cats). Can't understand that, but I guess they don't care about ruining the convertor.
Anyway, it may just be me wanting to feel a difference, but I did notice an improvement. How much, I can't really say, but it is noticeable in my case. I would've loved to make a few passes while at the track, but time didn't permit it.
It feels as if the low-end power hasn't changed much (below 3500 rpm) but above 3500-4000, the pull on the top end feels stronger. Now that the weather is cooling off some, I will have to try this again in a few weeks, and make a few passes just to see if it affects my times any.
In my opinion, it's worth a shot, just try it for yourself.

I've also discovered (upon experimentation once again) that different gasolines agree with my car more than others. Sunoco Ultra (94) is what I've been running most of the summer. I've switched to Amoco 93 for 2 tankfuls, and I'm surprised to see that the Amoco 93 and Sunoco 94 both seem the same.
I had switched to Exxon Supreme (93) for 2 tanks and complained to my wife every day about how sluggish the car felt ( I gassed up at the same station each time I switched brands) The Exxon felt like the car was missing about 10hp. I wasn't pleased with the Exxon Supreme at all.
I will give Mobil a try next, just to experiment once again.
Anyone else ever switched brands, any findings/feelings to report?
Thanks

Sorin

All Sunoco contains ethanol. Anybody knows how much? They say ethanol is good for reducing emissions. But is good for performance?