Map= manifold absolute pressure sensor. Guess the zr1 map helps with tuning. There was a debate about wether it is NEEDED but with it u can read boost througb your odb2 port. The zr1 plugs are just 1 step colder then stock which again not absolutely sure they r NEEDED. I think the sensor is about $40 and plugs $60-80.
ECS Novi 1500 supercharger, FSP cam, Tsp 2" longtubes, Squash dual pumps, Id850s, Aem meth, Jakes stageIII 4L80e, FTI 3600, ZL1 3.73 diff, BMR suspension, 17" weld rts 4.5" M&H skinnies front, carlyle racing 15" conversion mt 325 et street R. 10.41@133mph