This may mave already been beaten to dust or is already a sticky...if so, please blow this OP away, but...... I have been reading alot on the web about "tuners",(maybe too much) and quite frankly, it's sounding like a tuner should be the first step before any mods are made. I mean things like the ECU reading and managing drivshaft roations vs tire rotation, traction, Air / fuel mixtures, shift points, cam timing, cylinder spark etc. It sounds like the ECU is messing with alot more than I realized...and can the tuners actually over-ride the performance robbing things ? Fixing the speedo and clearing error codes is nifty, but what else can be controlled and modified by a $400 grade tuner ? I post this here because I have an 05 manual trans.