RENNtech HHT-Hand Held Tuner | ECU Upgrade | R199 | SLR McLaren | 675 HP / 646 LB-FT | M155 | 5.5L V8 Supercharged ferrari-458--2009-2015--esr3806621 740 LB-FT @ 4

740 LB-FT @ 4

Rated by RENNtech (peak @wheel):              665 whp @ 5

in addition to serving as an attractive under hood showpiece

structural laminates with controllable and predictable results

Performance BMC air filters are designed and produced to ensure a higher air flow than original paper filters

RENNtech HHT-Hand Held Tuner | ECU Upgrade | R199 | SLR McLaren | 675 HP / 646 LB-FT | M155 | 5.5L V8 Supercharged ferrari-458--2009-2015--esr3806621 740 LB-FT @ 4The RENNtech ECU Plus Upgrade brings the SLR McLaren up to 675 HP and 646 LB FT Gains: +47 HP and +25 LB FT. 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.