RennTech intermediate level ECU upgrade for the Mercedes M278 engine still offers huge gains in performance across the entire RPM range, but with a slightly reduced peak HP and torque from our standard tune.
This is ideal for customers who want increased performance in their daily driver without worry of extra strain on driveline components or for areas and countries with extreme altitudes, temperatures or fuel quality concerns.Â
RennTech intermediate ECU tune increases performance from 429 HP and 516 lb/ft torque up to 500 HP and 625 lb/ft at the crank! This is a slight reduction from our standard tune but still offers white knuckle performance at one of the most affordable price points in the tuning market.
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 14% Drivetrain loss on RWD vehicles.
Our numbers will be dependent on conditions and fuel quality. 91+ Octane gasoline is mandatory with this Performance Upgrade.
States known for poor fuel quality have to be supplied with a lower power setup
Features:
Gains: +52HP / +87LB-FT
Long-lasting and driver reliability
Significant gains in horsepower
Increases the performance
Significant gains torqueÂ
Increasing the engine's rev limiter
Incredible performance gains
Up to 500HP / 625LB-FT.
Stock Performance:
429Â HP @ 5,500rpm;Â 516Â LB-FT @ 2,000-4,500rpm
448Â HP @ 5,500rpm;Â 538Â LB-FT @2,800-3,900rpm
Modified Performance:
500Â HP @ 5,500rpm;Â 625Â LB-FT @ 3,700rpm
Vehicle Fitment:Â Â Â
2012Â Mercedes-Benz R231 SL 550
2013 Mercedes-Benz R231 SL 550Â
2014 Mercedes-Benz R231 SL 550
2015 Mercedes-Benz R231 SL 550
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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