PCA SDR

The TT team needs some info for planning purposes. We are attempting to find out the ratio of fuel purchases that are high octane unleaded fuel relative to 91 octane unleaded fuel (aka standard premium pump gas). Please, only answer this poll if you have run in a PCASDR-managed Time Trial in 2009 or 2010. Anyone else who's just dying to answer, PM me your poll choice so it doesn't goof up the poll sample. Better yet, come to a TT so you can be included in future polls.

After you answer the poll, please also make a single post to this thread with your answer (either "91" or ">91" will suffice), your class, and whether your car is registered for street use or not. For example, "91, OS, registered" or ">91, AR1, not registered". Two driver cars, both drivers should answer separately since you presumably use twice as much fuel as single driver cars. Please keep chit-chat out of this thread so it's easier for me to tabulate. Feel free to start another thread to discuss fuel types or other topics. Thread hijackers will get a 2 second penalty at the next TT . Thanks.

>91, X, not registered

91 Octane. GT3 "R Stock" class. Street legal. Too cheap to buy higher octane and probably wouldn't make a difference in my situation

91, GP, Registered.

91, 944spec, registered, I have not been buying gas at the tracks but at nearby gas stations

Greg Trigeiro

I mix 3:2 110 leaded:91 unleaded. Car is HI, not registered.

I usually bring a bunch of 110 because supply is not reliable.

>91, MSS, registered

91, KI, not registered

Unless they changed the rules, you can run "street" race gas (unleaded 100 octane from VP Racing and others) and take no points. I have found that if I am willing to pay the $50 extra for the fuel, the car definitely runs better. I was looking for the article I read a couple of years ago - in Australia, they tested a GT3 with regular fuel and 100 octane and measured a significant boost in power (15-18 HP, if I recall). The trick though is that you can't just show up with an empty tank and load it with race gas and go - your engine management system needs a while to get used to the "good stuff" (yummy...) and advance the timing to take advantage of the higher octane. If I am going to run in a major competition (e.g., David & Goliath shoot-out), I will run the tank down low, add about a half tank of 100 octane a couple of days before and drive it "spiritedly", then put in enough additional 100 octane for the actual race day. Zoom Zoom...

If your car is older and doesn't automatically adjust to the octane level, then obviously you would need to manually adjust for the fuel. Loading 100 octane in an engine tuned for 91 isn't going to do much (and could even cost performance, I suppose, since the slower-burning 100 octane is getting lit off "late").

One "beware" - going directly from 91 octane to 100 (and vice versa) may cause engine warning lights to come on (ask me how I know!). I now try to "blend" it in both directions. If they do come on, they should go out in a day or so - it is just that a drastic change in octane may result in a drastic change in the measured output through the cats and sensors.

A side effect is that the car really seems to run smoother on the 100 octane VP Racing - too bad I can't afford to run it very often. I haven't run with 100 octane since early last year, but if I could afford it, I would always run it.

91, HP, not registered and Kim gets + 2 seconds

>91, ISS, Registered

91, RS, not registered.

91, KI, Registered. (Times two for Tami and I)

>91,OI,not registered

91, GP, registered