this is a total thread hijack, but this is my S60R.... it LOVED 100 octane. I miss this car sometimes...

http://videos.streetfire.net/video/Volvo-S60R-Modified-by_16768.htm

it was a one of a kind. if you go to www.evolvecars.com and look at "the blue car" - i basically did that same car in titanium gray. it turned head whereever I went. it was fairly fast with m y mods - probably about as quick or slightly faster than a bone stock E46 M3. a new 335 with a chip would walk my old car..but 5 years ago - it was "cool". :)

Well here's my update. The car stopped belching grey smoke (it does that once in a while on cold mornings) with the 100 octane gas. My mileage stayed the same. No noticable increase in power. The most significant thing I noticed was the temperature of the engine. Usually the needle hovers just to the right of the midpoint of "8" of the 180 degree marker. With this gas, the needle was just a hair shy to the LEFT of the "8". Pretty interesting eh? So... my observation and subsequent conclusion will be I don't think I'll be buying it anytime again soon if all its going to do is run a few degrees cooler. :D

Conradtan: Good summation of your 100 octane experience.

Footnote:
We run 100 in a 1978 track car w/3.2 -- only because our very well experienced Indy told us the engine will run cooler and help the top end last longer. Not spending $13K on a rebuild too soon is motivation enough. But, to put 100 in a street car may not be cost effective.

Thanks, :cheers:
Ed