About LSSwapBible

LSSwapBible is a reference for swapping GM LS and LT engines into anything: engines, donor vehicles, parts lists with real prices, cams, calculators and answers.

Everything here comes from a database built from manufacturer documentation, vendor catalogs, published guides and aggregated owner reports — 1707 sources and counting, plus the real LS and LT tune files we read table by table. We keep the source behind every fact on file and check our work against it.

We are independent: not affiliated with GM, Chevrolet Performance or any parts vendor.

Who we are

LSSwapBible was started by a small group of mechanics who all tune, based out of Phoenix, Arizona. Our lead shop tuner signs off every Tune Report and every tune file before it goes out.

How we check our work

• Tune Reports and tune files: we read the exported tables and your logs, run the same checks every time, and compare your settings with the closest similar builds in our tune library. When the match is broad, or a fact about your build needs confirming, the report says so. Nothing is released until our lead shop tuner has reviewed and signed it off. A report is a starting point, not a substitute for a dyno tune.
• Guides and answers: every fact traces back to a source we keep on file. Owner dyno numbers are labelled as owner reports, not our measurements. How we source our data.
• Corrections: every page has a "Something wrong on this page?" link, or use the corrections page. We check the report against what we have on file and fix the page if it is wrong; on guides and answers the "Last updated" date moves when the content changes.