Down in the skunkworks of RGMotorsport’s Randburg HQ they’ve been working on a way to get the latest four-door version of the Jeep Wrangler to live up to the Unlimited part of its nomenclature. And it wasn’t long before they came up with a solution: they decided to supercharge it.
Not at all surprising, seeing RGM has a penchant for adding oomph with forced induction, preferring aftermarket supercharging thanks to the lag-free result a ‘blower’ provides.
Those in the know agree that the new(ish) 3.6-litre Pentastar V6 is a big improvement over the 3.8-litre lump it replaced, and the Pentastar is a modern design with features such as variable valve timing, which helps it to a useful 209kW in standard form, at a surprisingly high 6 350rpm. Still, the Jeep is no lightweight and has the aerodynamic efficiency of a breeze block, while its gearing is also on the looooong side.
In independent testing we recorded 0 – 400 metre sprint time of 17.9 seconds with a terminal speed of 125.5 km/h – respectable, but hardly numbers to set the world alight. In the 80 – 120 km/h flexibility test we recorded an 8.3 kickdown time.
But in RGM Supercharged form, the numbers tumble, but before we present the numbers consider this: the ‘after’ figures were achieved after 200-odd kilograms of accessories had been added; including a high-ride suspension kit, a winch/bumper kit, and an aftermarket rear bumper with spare wheel carrier.
And even in such a disadvantaged state our heavy breather is capable of a 0 – 100 in 8,7 seconds, a 0 – 120 km/h sprint of 12,2 seconds (exactly 4 seconds faster than standard) and a 0 – 400 metres time of 16,5 seconds at a speed of 136 km/h. It also knocked a worthy 1,4 seconds off the 80 – 120 km/h test, suggesting that overtaking is going to much less stressful, as will towing.
The real-world numbers are impressive and so too are what we recorded on our rolling road dynamometer: we measured 215 kW at 6 500, translating into 316 kW at the flywheel – that’s 101 more than standard! There’s also an estimated 475 Nm at 4 300 rpm (where the standard car has its 347 Nm peak) and our car peaks at 517 Nm@ 5 500rpm. At 2 000 rpm we had already matched the maximum torque output of the standard engine...
The outcome is an engine far better suited to the five-speed automatic transmission, especially at Highveld altitude where the tall ratios and peaky nature of the engine conspire against it. With RGM’s reputation for quality workmanship, installation excellence and attention to detail, it adds real value and makes for Unlimited potential for the big Jeep…
The full installation comprises a Vortech supercharger and all ancillaries, Techniflow exhaust system (designed and manufactured in-house), Unichip Q engine management piggyback computer and a serviceable free-flow air filter element and costs R105 000 including VAT, installation and six-month 20 000 km warranty.
STORY COURTESY OF ROADWORX COMMUNICATIONS