The general rule
If you’re running a mass-air Fox EEC-IV or any system that still treats air-charge temperature as a minor trim and doesn’t directly tie it to spark load modeling — keeping the IAT pre-compressor is simplest and stable.
If you’re running a modern speed-density ECU or a tuner that scales spark directly with IAT (Coyote, Terminator X, Holley, etc.), the correct, safest, and more accurate location is after the intercooler or as close to the throttle body as possible.
If you’re running a mass-air Fox EEC-IV or any system that still treats air-charge temperature as a minor trim and doesn’t directly tie it to spark load modeling — keeping the IAT pre-compressor is simplest and stable.
If you’re running a modern speed-density ECU or a tuner that scales spark directly with IAT (Coyote, Terminator X, Holley, etc.), the correct, safest, and more accurate location is after the intercooler or as close to the throttle body as possible.