With stock outputs of 522 kW and 875 N.m of torque, the Jeep Grand Cherokee Trackhawk is already a well-endowed performance SUV. However, the tuners over at Geiger Cars believe those figures just aren't high enough, which is why the firm has developed a new tuning package that takes the vehicle to another level.

Dubbed the Gulf 40 (marking the tuner's 40th anniversary), the modified Grand Cherokee Trackhawk’s 6,2-litre V8’s supercharger has been upgraded to a Magnuson TVS 2650 system which raises the boost pressure from 0,8 to 1,1 bar. The block, meanwhile, has been fitted with stronger forged pistons on steel conrods. Additionally, the software has been tweaked.

The result? Peak outputs of 662 kW and 1 003 N.m (even more than the Manhart Performance upgrade we've already featured), which gives the Trackhawk a top speed of 312 km/h (the claimed 0-100 km/h time has not yet been announced). Power is directed to all four wheels via an eight-speed TorqueFlite automatic transmission.

To improve the handling, the Trackhawk gains lowering springs (dropping the body by 25 mm) and a set of 22-inch light alloy wheels wrapped in 315/30 R22 rubber.

Gieger Cars is selling the Jeep Grand Cherokee Trackhawk Gulf 40 as a "barely used" second-hand vehicle for €129 000 (that's around R2,2-million).