Not sure what to tell you about the idle, put the high RPM's @ start up is the accelerated warm up (dumb idea on mazda's part). Although that's only supposed to be around 3000 rpm...
N/A's run rich stock even in good condition, w/ an SAFC or Rtek you can prolly get 15 hp just from trimming the fuel maps.
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"If losing you are yet no mistakes you have made, a different game you should play" - Yoda
