aih mod. removing the air intake heater from the intake. the AIH is designed to reduce emissions by heating the air going into the engine at certain cold air, low rpm conditions.
The benefits are not measurable on a dyno, although from looking at it you would think it would help.
99.5 Superduty Crew 4x4 6 speed Smokewagon
Pizza cutter tires, Tymar, BTM, DP
If it don't run, chrome it.