Do I need a retune after a cam swap?
Yes. A cam changes how much air the engine takes in at every rpm, so the stock calibration no longer matches it.
The tables a tuner revisits, per LSX Magazine and HP Academy: desired idle speed, idle airflow and idle control limits, VE/MAF fueling (the stock idle-region VE is wrong after a cam swap), spark, and torque modeling. On AFM engines that had the AFM hardware removed, the deactivation function also has to be turned off.
See cam tuning.
Want to do it yourself? See who tunes it, and how to learn.
Confidence: medium — sources disagree or are limited; check the sources below.
Related questions
- Why would VATS and starter checks refuse to disable on an E38 ECM even after a Write Entire?
- What is the exact procedure to disable DoD/AFM in the tune without a mechanical delete kit?
- How do I set up 6L80E part-throttle and WOT shift tables after a gear and tire change in an engine swap?
- How do I add a real flex fuel sensor to an E38 Camaro and dial in E85 — what needs adjusting beyond enabling multifuel?
- What is needed to segment-swap a 4L60e E38/T42 truck to a 4L80E?
- Does simply selecting 4L80E under the transmission tab convert a 4L60E tune, or is a segment swap required?
Sources
- DOD, AFM, And DFM Deletes: A Q&A With Michigan Motorsports — LSX Magazine
- LS Tuning For Optimum Performance — LSX Magazine
- Project Corn Star: Tuning An LS For Boost With HP Tuners — LSX Magazine
- LS Idle Tuning Basics With HP Tuners — High Performance Academy