RENNtech | ECU Upgrade | SL 450 AMG | R231 | 402HP/454LB-FT | 3.0L BiTurbo V6 | M276 porsche-718-cayman--my2016-18--esr3545487 CLASS S LONG (W 221)

CLASS S LONG (W 221) 351 V6 4-Matic Blue Efficiency (HP: 306 | Year: 11 > )

By ensuring the internal header bore surfaces are smooth

8L DFI Stock Performance:

it can produce more noise than a street tech kit

Rated by RENNtech (peak @wheel):              687 whp @ 6

RENNtech | ECU Upgrade | SL 450 AMG | R231 | 402HP/454LB-FT | 3.0L BiTurbo V6 | M276 porsche-718-cayman--my2016-18--esr3545487 CLASS S LONG (W 221)RENNtech ECU Upgrade for 231 SL 450 AMG BiTurbo. Up to 402HP and 454LB FT. Gains: +40HP & +70LB FT RENNtech M276 Biturbo ECU Upgrades are TV approved! RENNtech tuning products are certified to meet CARB standards in all 50 States. 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