come to think of it depending on where you are the regular unleded octane is different. some places its 87 and some places its 89. I wonder what mitsubishi's idea of "regular unleded" is?

 

premium

 

Sorry it wouldnt let me add the image to my last post. But I dont think that would go out of their way to put this on every car unless they had a good reason

 

Just read the manual, it says, " Your Vehicle is designed to run on unleaded gasoline only, having a minimum octane rating of 87."

All that little sticker means is use Unleaded gas only. Not which grade of unleaded.

I've been using Amoco Ultimate and it has made a big difference in my performance. Especially with the A/C running. Regular Unleaded, the car was a real dog. As soon as I put in the Ultimate, bam.. much better response. The only modification I have is an intake.

Just check the manual though.

 

I use 89, I found out I do worse milage with the best gas, and my car performs better with 89, the "middle class". Oh, and to me mobil and chevron get you the best gas milages.