RENNtech ECU Upgrade | R231 | SL 550 | 500HP / 625LB-FT | 4.7L V8 BiTurbo | M278 porsche-911--991-1---2011-2016--turbo-esr5301476 The maximum power number reached

The maximum power number reached with the RENNtech ECU+ Upgrade for the C205 - C 63 AMG Coupe is up to 601 HP and 657 LB-FT

6 Series (E63) M6 V10 [Full kit] (HP: 507 | Year: 05 >)

-High strength to weigh ratio

Up to 514HP and 566LB-FT

SLK 55 (R171) Stock Performance:

RENNtech ECU Upgrade | R231 | SL 550 | 500HP / 625LB-FT | 4.7L V8 BiTurbo | M278 porsche-911--991-1---2011-2016--turbo-esr5301476 The maximum power number reachedECU Upgrade 500HP 625LB FT Gains: +52HP +87LB FT Our 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