If the RX-8 engine is running really rich, what are the drawbacks to having it eventually leaned out? Shouldn't we have more HP and better fuel economy? Sounds a bit contradictory, is it possible?

 

yes, this is precisely what we're waiting for with an ECU reflash/ chip replacement.

it's been there from square one.

 

Now are we hoping this reflash / replacement will be Mazda provided or is it most likely going to be aftermarket. I am hoping Mazda recognizes and does it, so that our warranty's are intact.

Also how much can we hope to gain from leaning out the mixture?

 

completely speculatory. at most?? 12-15 is probably the best you could do (bumping it back up to the 240 flywheel hp range).