MadEvo89

My first mod was a reflash only. There's a big difference from stock.

boostedwrx

iTrader: (27)

There are tons of mods that wouldn't require a tune though - basically anything that doesnt change airflow.

-Lighter wheels, rotors, or possibly an alignment (hah Dave).
-Any other lightweight mods
-Grounding kit (haha)

mathgeek

Is the factory air/fuel ratio optimal? I've been working under the assumption that what is stock is best. Everyone says that the Evo runs too rich from the factory. Forgive me, but I have a hard time believing that all of the engineers at Mitsubishi, with their Ph.D's in mechanical engineering and such, missed the boat. There has to be a reason why stock settings are what they are. If an aftermarket tune is so great (and it does seem to produce gains and not compromise fuel economy), why doesn't the Evo come with it already? Is it an emissions issue? Does a tune, while providing more get up and go, hurt the engine in the long run? Mitsu will void a warranty if they detect it. If it's so awesome, why would they do that?

I'm not being combative. I've just always wondered about this.

Soon2BEVO

iTrader: (41)

Its to keep it safe even if lets say 87octane were dumped in the tank. Its about covering their asses for warranty purposes. The EVO's AFR is nowhere NEAR optimal in stock form for performance or fuel economy.