I'm not getting my work done at the dealer I bought from. It'll be from the nearest Mitsubishi-certified garage. And I don't trust them to not void my warranty, so I'll keep my mods superficial.

On a side note, it seems like my mpg is lacking. I probably got maybe 150 or 160 miles on a half tank - is it the winter weather or what? I saw the epa listed fuel estimates for my car but I didn't believe them. It almost seems like it isn't quite living up to those either, which is pretty bad, and I know it's not my driving style. Any ideas as to what it could be? Maybe the fuel reserve is bigger than in my last car, which had the same size gas tank, and that makes it seem like gas is being used up faster...

 

This is what the dealer told me when I complained about my mpg, but I have AWD and more weight than your car:
"When your car exceeds 3000 rpm's there will be more fuel consumption due to it being a MIVEC. If you minimize the time that you are above 3000 rpm's you will notice a big difference"
I tried that and sure, maybe I got 10-20 more miles per tank, but damn, I could walk faster. The fun is after the cam profiles switch over and the engine utilizes the MIVEC technology. I am supposed to get 21mpg city I believe and 26 highway....NEVER happened, not even close. My best avereage MPG for mixed 60% freeway and 40% city was 19 mpg. But again, the AWD is heavier and more power lost to the drivetrain. My current average is about 17-18 mpg(220-240 miles per tank), but there are very short freeway on-ramps.
Check your air filter, tire pressure and all the basics, though I don't think it'll help that much. The dealer can do a "fuel consumption test", that's what they called it when they checked my air fuel ratio and ensured there were no leaks in the system.

 

I'm sure it's the RPMs like you say. I tried to keep them down and it seems to help. But I have to ask (I saw the MIVEC profile on the Mitsubishi site), what's the point of a MIVEC having the characteristics that it does? It seems to just make the engine rev higher and lose fuel economy.

 

If you drive the non mivec 2.4 you would notice a big difference. It was designed to offer more power at lower rpm's and substantially more at higher rpm's. Once the cam profiles switch over the air and fuel mix leans out making the extra boost of power. Some say it's like a really small turbo boost. Personally i'd like to eliminate the initial cam profile and keep it more lean, but I'm going to get a piggyback hopefully soon to fix that. It is also supposed to offer better fuel economy, but every car out ther is a couple mpg lower than posted... the ones I've seen and heard about anyway. Take the good with the bad.

 

Interesting. Well that explains a lot. Unfortunately, most of the area below 3k RPMs is rather weak, but at least I know where to keep things for better fuel economy and where to put it for performance. Out of curiousity, would it make a bigger difference if the 2.4 MIVEC was a DOHC instead of a single?

 

Dont know the answer to that, but if you change the cam it has it may help
But yes, below 3000 rpm's the car is okay, but you'll notice a "jolt" of power once you hit 3000 rpm and it carries pretty well from there. I have autostick trans, so when I want to play, i keep it in the 2500+ rpm's....Mobil loves me for that!