Exhaust out is as important to the flow system as air in. T&B looked to the Mopar experts at Tube Technologies in Corona, Calif., for a set of their proven 2-to-2.125-inch step headers. Note the EGT fittings, used for testing the combination. "The EGTs let us check the exhaust temperature to make sure we didn't have a cylinder that was too far off the others, and just making sure everything is consistent. Although you have your air/fuel ratio on the dyno, it's nice to have them as a backup check."