Locate an Auto Repair Shop in Kunia, Hawaii

Hop on the next flight to Hawaii and we'll do it. I'll even let you drive! Short of that, I challege all MZ3 2.3L drivers to try their own tests...

Again, you're not listening closely. I'm saying it runs better on premium than regular. Not necessarily faster. Just better. Smoother, less hesitation. Maybe the 5 tanks of regular I got from five different stations was lousy...or maybe I got the one car that is programmed to run better on premium, like the MZ3's in Australia. Their compression ratio is also 9.7:1 like the U.S. models. And if I write an article, I'll write it for Popular Sarcasm, or maybe Car & Idiot. Meantime, I'll drive my car, and ya'll drive yours.

The manual says regular or higher grade.

...first of all, if you haven't driven the Mazda3 with different grades of gas, then you don't have a basis upon which to comment...and is often the case in life, it's best to experience something yourself rather than rely on the opinions of those who perhaps are guessing. I'm not saying premium makes the car run better. I am saying after 22 tanks that premium makes the car run best. If any of you want to run regular, that's cool. All I'm saying is try a tank or two or premium and judge for yourself. Too much hand-holding, paranoia and mindless economizing on this board...by people who don't own the car.

I have the 2.3L with the five speed. I've run 6600 miles so far, approximately 15 tanks with premium, 5 tanks with regular and now two tanks with premium again. Say what you will, but seat of the pants tells me the car revs smoother and quicker, and displays more immediate torque using the premium. It tends to hesitate on regular. So while this is a topic of much discussion, at least for this car, I say run a few tanks of each, and judge for yourself. My butt tells me premium brings out the potential of the motor better...