Engine swap questions - 24x vs 58x and harness compatibility?

The rule: the crank reluctor, cam sensor, computer and harness all have to match.

24x (Gen III: LS1, LS6, LQ4, LQ9, Vortec trucks through 2006) uses a 1x cam sensor; 58x (Gen IV: LS3, LS7, L76, L92, 2007+ Vortec trucks, 2007+ LS2) uses a 4x cam sensor. Exception: 2005–06 LS2s are 24x, so they need a 24x harness and computer. PCM, harness and sensors must match; a Gen III PCM on a 58x engine needs a conversion box.

Tell them apart: Crank reluctor is 24x or 58x; the ECU must match. Tell by the crank sensor (behind the starter): early black 24x, later gray 58x.

Running a 58x engine on a 24x harness/computer:

• The Lingenfelter TRG-002 module lets a Gen IV GM V8 with a 58x crankshaft trigger wheel and 4x camshaft timing gear run in a vehicle wired for the 24x crank / 1x cam system without opening the engine. It is plug-and-play to the existing harness and factory sensors and has its own power source harness.
• The TRG-002 only converts a 58x crankshaft signal to 24x; no module exists to convert 24x to 58x, so that direction requires physically changing the reluctors. The module does not work with front-wheel-drive LS applications.

The reverse (a 24x engine on 58x electronics) needs the reluctor changed physically. See swap tune checklist.