I just posted something about fuel grades in the gas price thread. For those of you who INSIST that you must use premium( all you Hi-po GT people)..read this.
http://www.usatoday.com/money/autos/...emiumgas_x.htm
You cars will run FINE on regular, you just wont haver as much performance. I thought people knew this. If you have it modified, then you more than likely have to use premium. But if all you have is a boost controller, then turn it down to stock boost levels & you will be fine.
I used to tow ALOT of stuff with my old V8 Tundra & used ONLY regular fuel. There was NEVER any noticable difference between the two grades of fuel. I could tow my VR4, parts, a loaded bed & 3 people & still be able to pass people on the interstate with no trouble at all. Alot of time the power actually suffered when I used premium.
**Ofcourse** if you choose to run regular, then you may run into preigintion problems. The best thing to do is gauge it yourself. Put in a 1/2 tank or so. If it works fine then just keep adding reg. If the preigintion gets to bad for you. Then add some premium. It's kinda a guessing game as each engine is different. I know quite a fe waround here with Hi-po's that run reg with no troubles.