Can I swap a 58x Gen IV engine in place of a 24x Gen III engine without changing the ECM?
Yes. 24x (Gen III) and 58x (Gen IV) engines use different PCMs, harnesses and sensors (24x crank with a 1x cam sensor, vs 58x crank with a 4x cam sensor). If the vehicle is set up for Gen III, either keep a 24x engine, or run the Gen IV engine with its own matching PCM and harness. Running a Gen III PCM on a 58x engine requires a signal conversion box, which adds complexity.
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No, a 58x Gen IV engine won't work directly with a 24x Gen III ECM because they use different strategies. We recommend replacing a 24x engine with another 24x engine. A Lingenfelter converter box (TRG-002 style) can translate the Gen IV cam and 58x crank signals for a Gen III ECM, but at almost $300 (February 2020) it's often cheaper to just buy an engine with the correct reluctor already installed.
Check this first:
- Confirm the reluctor wheel (24x or 58x) and crank/cam sensor type before buying the engine
- Confirm what your existing ECM expects
Based on what we've seen work across our own builds, our friends' builds and the wider LS community, reviewed by our lead shop tuner (over 20 years of LS and LT tuning experience). Every combination is different, so use at your own risk.
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Check this first
- Confirm you actually have a 24x block (sensor PN, not just color)
- If you have a 58x engine, this product does not help - you need a 58x-compatible PCM or a Lingenfelter box
Try this, then this
- Verify reluctor first (REC-150) — wrong generation = wrong part. Worked if: 24x confirmed
How you know it's fixed
- 24x confirmed, sensor relocated, PCM syncs
Still not fixed?
- For 58x engines, look at the Lingenfelter TRG-002... no - look at the Lingenfelter 58x-to-24x conversion module instead
Every option we know of
We may earn a commission when you buy through links on this page.
| Maker / product | Part # | Fits | Price | Where | Status / notes |
|---|---|---|---|---|---|
| Lingenfelter TRG-002 crank trigger relocation | TRG-002 | Gen III 24x blocks | $304.95 | Buy c6performance.net | In production does not convert 58x to 24x |
Prices are approximate as of September 2026. We list every option we know of, including small shops and used parts we can't link to. Confirm fitment with the seller.
Time and cost: Ships in days
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