Custom ECU Tuning for 2002-2010 Chevy Trailblazer GMC Envoy Buick Rainier Olds Bravada Saab 9-7X 4.2L I6

Description:

Custom ECU and TCM tuning for 2002–2010 GMT360 platform vehicles equipped with the 4.2L Vortec I6 (LL8 Atlas). Typical results include 20–30 HP gain, 2-4 MPG improvement, smoother throttle response, better drivability, and stronger acceleration.

Supported Vehicles:

• Chevrolet Trailblazer (2002–2009)

• GMC Envoy / Envoy XL / Envoy XUV (2002–2009)

• Buick Rainier (2004–2007)

• Oldsmobile Bravada (2002–2004)

• Isuzu Ascender (2003–2008)

• Saab 9-7X (2005–2009 — non-V8 variants)

Important Notes:

• 2008+ automatic models have a separate Transmission Control Module (TCM). If sending in your PCM for programming, please include the TCM as well.

• Speedometer correction

• Rev limiter raise

• We strongly recommend running 91+ octane (premium) fuel. Many 4.2L I6 engines experience spark knock on 87 octane with the default factory tune. Premium fuel allows for more aggressive timing, which improves both power and efficiency.

What's Included:

Full engine and transmission calibration tailored to your vehicle's setup. We adjust the calibration based on your modifications, octane preference, and driving needs.

What We Can Adjust:

• Fan 1 and Fan 2 activation/deactivation temperatures (2008 - 2009 Only)

• 90-second key-off fan run (2008 - 2009 Only)

• Transmission type change (4L60E, 4L80E, manual, or non-electric automatic)

• VATS / Passlock security delete

• Axle ratio change

• Tire size correction

• Speed limiter removal

• Torque management / torque abuse mode adjustment to eliminate launch bog

• Unused engine code suppression (specify in order notes which codes to disable)

• Wide-open throttle (WOT) fueling adjustment

• WOT spark timing optimization

• Raised rev limiter

• Raised shift points

• Downshift table adjustments to remove throttle lag

• Increased transmission line pressure

• MAF calibration (year-specific)

• Power Enrichment (PE) engagement adjustment to reduce knock retard

• Torque converter lockup table refinement to extend transmission life and eliminate TCC hunting

• VIN correction

• E85 flex fuel enable

• V8 swap support (5.3L, 6.0L conversions)

Emissions Removal Notice:

Emissions equipment deletes (rear O2 sensors, catalytic converters, EVAP, EGR) are intended for off-road, race, or competition use only and are not legal for street-driven vehicles. Customer is responsible for compliance with all applicable federal, state, and local laws.