Description:
RennTech HHT (hand held tuner) allows you the unlimited ability to switch between tuned and stock ECU programming and requires no ECU removal. RennTech proprietary tuning module stores both the RennTech tuned file and your vehicles stock file. The module plugs directly into the OBD2 port and delivers the file you choose directly to the ECU. Programming takes only a few minutes and the vehicle can be reflashed at any time as many times as you wish.
RennTech HHT (hand held tuner) allows you the unlimited ability to switch between tuned and stock ECU programming and requires no ECU removal. Our proprietary tuning module stores both the RennTech tuned file and your vehicles stock file. The module plugs directly into the OBD2 port and delivers the file you choose directly to the ECU. Programming takes only a few minutes and the vehicle can be reflashed at any time as many times as you wish.
RennTech proprietary ECU upgrade for the Mercedes M278 Biturbo engine offers huge gains in performance across the entire RPM range without sacrificing around town comfort or daily driver reliability. With the newest update of their Software Upgrade for the M278 "“ 4.7L V8 BiTurbo, RennTech boosts the 550-Series to AMG Power Levels. The RENNtech upgraded M278 now produces up to 540 HP and 705 LB-FT at crank.
Compared to power numbers by Mercedes-Benz, the GLS 550 gains up to 66 HP and 167 LB-FT. This Software update delivers up to 10 HP and 99 LB-FT more than the previous version. The vast amount of increased torque across the entire RPM range gives the 550 an extra edge to compete with AMG powered vehicles. All this without sacrificing around town comfort and daily driver reliability.
Attention:
We have found the M278 engine stock performance numbers vary from the baseline figures claimed by Mercedes Benz. We typically see higher baseline numbers than claimed by the factory.
Power gains are calculated based on stock numbers measured by RennTech
Crank Performance Numbers are calculated with a 18% Drivetrain loss on 4MATIC SUVs.
Our numbers will be dependent on conditions and fuel quality. 93+ Octane gasoline is mandatory with this Performance Upgrade.
States known for poor fuel quality have to be supplied with a lower power setup
Features:
- Provides ability to switch between tuned and stock ECU programming
- Providing comfort or daily driver reliability
- Significant gains in horsepower
- Increases the performance
- Significant gains torqueÂ
- Gains: +66HP / +167LB-FT
Stock Performance:
- 449 HP @ 5,500rpm; 516 LB-FT @ 2,000-4,500rpm
- 474 HP @ 5,500rpm; 538 LB-FT @2,800-3,900rpm
Modified Performance:
- 540 HP @ 5,500rpm; 705 LB-FT @ 3,700rpm
- 433awhp @ 5,500rpm; 578awtq @ 3,700rpm
Vehicle Fitment:Â Â Â
- 2016Â Mercedes-Benz X166 GLS 550Â Biturbo
- 2017Â Mercedes-Benz X166 GLS 550Â Biturbo
- 2018Â Mercedes-Benz X166 GLS 550Â Biturbo
- 2019Â Mercedes-Benz X166Â GLS 550Â Biturbo
- 2020Â Mercedes-Benz X166Â GLS 550Â Biturbo
Note:
Images are for representation purpose only and may differ depending on application.
⚠️ California Proposition 65 Warning:
This product may expose you to chemicals known to the State of California
to cause cancer or reproductive harm.
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Flexible Returns:
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Unused items in brand-new, original packaging can be returned within 30 days. While standard refunds incur a 25% restocking fee, we will waive this fee entirely if you choose store credit or an exchange for your next upgrade.
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Exclusions:
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To ensure every customer receives brand-new, untampered components, parts that have been installed, modified, or used are non-returnable. Custom builds, special orders, and wheel/tire packages are considered final sale.
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