Re: Dumb gas question, but... (eggie)
91 doesn't even do it, and 87 would be a crime (and against what is in the owner's manual; but I'm not unable to imagine a dealer skimping...)
What the car needs to generate full hp is at least 93, and it seems to take full advantage of possibly a bit more than that while stock -- and yet again even more if it has been chipped or otherwise modded.
For the past 18-months I've been boosting the octane of that cr*p that passes for "premium" gas in CA by a) finding a place that sells 100 octane unleaded and mixing in 5-gal per fill-up, or b) using Torco, which is a very effective octane booster.
The increase in power -- and especially midrange torque -- from feeding this car proper octane has to be experienced to be believed. The R is neutered on 91. It pulls like you'd thought it should, and more, on 94-95+. The engine actually adopts a distinctly different intake and exhaust note. It simply cannot possibly come close to its rated power on 91, especially with summer heat reducing the efficiency of the intercooler.
100 octane unleaded has the disadvantage of significant inconvenience. You first need to find a station that sells it (I lucked out and have one a couple of miles away). And then you have to do something like buy a few 5-gal gas cans to take it home, or else you are umbilicalled to this gas station.
Torco has the advantage of being very portable (20oz-24oz per tank will do it), but you will have to clean or change the spark plugs more often, since the MMT used for octane boosting fouls them more quickly. Some people are put off by the whole idea, and I can appreciate that.
Anyway, the topic has been discussed to death here in many, many posts. Do a search for 100 octane and/or Torco in both the forum and the forum archive.
I've sold my soul to the high-octane devil. The car is simply an AWD T5, maybe not even that, without at least 93 octane. If I am unable or unwilling to obtain at least 93-94 octane for the R, I will sell it. It makes that big of a difference.
