[pampadori]

My opinion - 100% do ignition and fuel.

Its not even about the max power, its so much better at part throttle torque and fuel efficiency. You cruise at 70mph only opening the throttle about 5-10%.

With fully programmable ignition you can run ~40-45 degrees of advance and run quite lean to get a nice bump in MPG. It will feel much more torquey at part throttle since you can run more advance too. Just opens up so much more tuning ability. Nailing the AFR is the easy part and isn't really where power is made so the more attention you can give the ignition events the better.

You can also be prepared for the corn juice future and add a flex fuel sensor and blend your maps based on the level of ethanol in the fuel. That reality might be a few years off but who knows. Might be a requirement sooner than later.

Ok, just my opinion and I'll shut up now.