THE Jeep Grand Cherokee Trackhawk is an exercise in excess, with the Dodge Hellcat engine wedged behind its snout producing 522kW and 868Nm for supercar-slaying performance.
Well, for one Texan, that wasn’t quite enough. By now you should be familiar with John Hennessey and his tuning company, which has a reputation for fettling already powerful cars to produce unhinged monsters.
Video review: 2018 Jeep Grand Cherokee Trackhawk review
His latest creation is the HPE1200 (catchy name), which is a kit available for the Jeep Trackhawk. And the results are, well, predictably eye-opening.
The HPE1200 involves fitting upgraded pistons, rods, ported cylinder heads, a new camshaft, long-tube stainless steel headers, and a larger 4.5-litre supercharger - the latter of which pumps 22psi of boost.
The end result is a dyno-tested 748kW, along with 1209Nm of torque. Hennessey calculates this to be 895kW/1491Nm at the crank.
The upgrade drops the Trackhawk’s 0-60mph (97km/h) to 2.3 seconds, while the quarter mile is taken care of in 9.6 seconds at 233km/h.
When we performance tested the standard Trackhawk at Winton earlier this year, we cracked the quarter mile in 11.6 seconds, with a trap speed of 186km/h. The 0-100km/h sprint was reeled off in 3.7 seconds.
With that context provided, Hennessey’s upgrades become all the more staggering, cutting a full two seconds of the 400m dash.
For further comparison, a McLaren 720S takes around 10 seconds the complete the quarter mile. Same goes for the 515kW Porsche 911 GT2 RS.
We should mention that our test of the Trackhawk – which, admittedly, included time on Winton’s rallycross track – obliterated the record for single day fuel-consumption on a Wheels test, with deputy editor Andy Enright reporting 49.7L/100km. We don’t even want to think about the size of the fuel bill the Hennessey would produce, particularly since it’s tuned to guzzle 109-octane jungle juice.
Read next: 2018 Jeep Grand Cherokee Review
And there’s a caveat to the incredible straight-line performance achieved by the Hennessey Trackhawk. Its numbers were achieved with Nitto 555R 275/40R20 drag radials fitted to each corner. Not exactly street-appropriate rubber.
Want one? Hennessey is building just 24 HPE1200s, setting you back US$179,000 (A$250,657) each, or a miserly A$280 per kW.
It’s a bargain when you consider you’d be able to embarrass McLaren 720S owners for half the price.