Jeep JK Hemi V8

Jeep JK V8

Mark Clancy caught the Jeep bug more than 20 years ago and he hasn’t been able to shake it.

As a young bloke he was into some pretty serious hardcore off-roading, and he admits to ownership of “probably around 25 Jeeps”, many of which were heavily modified.

Now, as a family man, Mark says he’s more into general touring. “We used to do a lot harder stuff back in the day, but now having [a] family, we don’t do as much,” he claims with a laugh. When pressed a little more on the subject, though, Mark admits: “We still like to play a little bit hard… but yeah, we’ve still got to drive the car home.”

The car Mark’s referring to isn’t your average tourer. Sure, from the outside it looks only slightly modified, but lurking under the bonnet is a 5.7-litre Hemi V8 that makes this JK Unlimited a serious piece of kit or, as Mark describes it, “a go-fast tourer.”

Jeep JK V8 3The thing that attracted Mark to the Jeep brand in the first place has also played a big part in the reasoning behind this vehicle’s V8 conversion: availability of aftermarket parts. You see, Mark kicked off his four-wheel driving habit in a Daihatsu F20, moved on to a Suzuki after that and then a Land Cruiser, but eventually he discovered there were more off-the-shelf bits and pieces available for Jeeps than Japanese brands.

“I just liked the aftermarket parts you could get for Jeeps. It was easier to do Jeep stuff back in the day; getting stuff for Nissan Patrols was just too expensive. It was easier to buy old Jeeps and then spend too much money on them,” chuckles Mark.

And that’s still the case today; dropping a V8 into a Wrangler is as simple as buying a JK Hemi Kit from respected US-based company American Expedition Vehicles (AEV), and then finding someone with a basic mechanical understanding to do the job. Yep, AEV says this conversion kit is simple enough for do-it-yourself types, and it includes everything you need to complete the swap with factory-like results.

Jeep JK V8 4To make the engine swap as easy as possible, the AEV kit includes no-measure engine mounts, a fitted exhaust system, a custom radiator and a plug-and-play wiring harness that uses OE connectors and factory colour-coded wires. Mark employed the services of the boys at Jeep Konection and Dyers Auto Engineering to do the V8 conversion on his 2007 JK Wrangler, as well as perform a host of other modifications.

The engine is factory standard, though its claimed 260kW and 530Nm on tap is a marked improvement over the standard 3.8-litre V6, which could only muster 146kW and 315Nm. All that V8 grunt drives through a heavy-duty Jeep/Dodge automatic transmission and then on to the standard JK Wrangler transfer case. The factory diffs have also been flicked in favour of Dynatrac units.

Jeep JK V8 7“The front diff is a Dynatrac 44 with 35-spline shafts, ARB Air Locker and RCV [Performance Products] universals,” Mark says. “The rear is a Dynatrac 60 with 35 splines and ARB Air Locker.”

So how does it go on the road? “Yeah, good,” Mark says in a most understated way. “I reckon it drives better than a factory Jeep.”

And you can bet this thing is a monster off the road, too, thanks to that Hemi V8 power, front and rear lockers and the aggressive 37-inch Pro Comp Xtreme Mud Terrain tyres on bead-locked AEV rims.

Jeep JK V8 11There’s loads of ground clearance for difficult off-road terrain thanks to an AEV DualSport suspension system that gives this beast a 3.5-inch lift. As well as springs, the AEV kit includes Bilstein 5160 remote reservoir shocks, geometry correction front control arm brackets, a custom bent rear track bar and rear stabiliser end links, as well as a host of other components that ensure correct suspension geometry is maintained despite the significant lift. 

As a result, AEV claims the kit brings “OE-level suspension engineering to the aftermarket… one that is both extremely capable off-road, while offering unparalleled on-road performance and handling.”

Jeep JK V8 10Mark is a big fan of AEV gear, as there’s a lot more of it on this rig, including the front and rear bars, the wheel carrier, the fuel caddy, hi-lift jack holder, bonnet, snorkel and corner guards. “I like the AEV product because it still keeps the car looking factory, in a way,” Mark says. “It doesn’t make it look like a big rock crawler.”

This JK is not just a one-shop catalogue special, though. To ensure there’s maximum wheel travel off-road, Mark’s fitted a Currie Antirock front sway bar. The Antirock, which doesn’t need to be disconnected for off-road use, is designed to increase off-road traction by balancing and distributing the vehicle weight over all four tyres.

Other aftermarket accessories that have managed to find their way on to this JK Wrangler include the bar-mounted Warn 9.5ti winch and a pair of KC POD carbonfibre 70W HID driving lights, while up top there’s a Front Runner roof rack and a Foxwing awning. Down below, there are Mopar Enhanced Rock Rails.

Jeep JK V8 9Mark put his own manufacturing skills to use on the inside, fabricating his own drawer system and fridge slide for the ever-reliable Engel. Above this is a cargo rack from US-company Adventure Trailers, which allows Mark to make use of every available cubic-inch of cargo space in the back of the Jeep. 

Adding to the versatile nature of the JK Wrangler’s rear-end is a nifty drop-down table on the tailgate that was also sourced through Adventure Trailers. Called a Trailgater, it’s manufactured by a company called Outback Adventures, and is cleverly designed so that it can be installed without drilling any holes in the tailgate – you don’t even have to relocate the subwoofer. Remove a pin and it simply drops down for use, and the slide-out cutting board can be easily removed for cleaning.

Jeep JK V8 5Fitting electrical accessories to complex modern vehicles has become increasingly difficult and the JK Wrangler is no exception. To avoid the need to cut into any factory wiring, Mark has installed an sPOD system, which is mounted on the roof between the sun visors.

“The sPOD system has its own separate fuse box and relay system,” Mark says. “It’s a bolt-in system. It controls a light for the back, lights for the roof [not fitted at the time of the photo shoot], UHF, GPS, fridge, all the accessories I have in the car go through that; anything that runs off the second battery.” Making sure all the electrical accessories receive a reliable source of power is a Redarc BCDC in-vehicle battery charger.

In place of the standard rear-view mirror, Mark has fitted a screen that can be manually switched on when required and comes on automatically when reverse is selected. A Hema Navigator makes sure Mark doesn’t get lost in the bush and an Icom UHF is used for vehicle-to-vehicle comms. 

Jeep JK V8 8Being Melbourne based, Mark does plenty of off-roading in the Victorian High Country. Without too far to travel to get into the scrub, touring range hasn’t been much of an issue with this big petrol-powered vehicle, despite the Jeep’s brick-outhouse aerodynamic package and the potent Hemi V8. In fact, Mark reckons fuel consumption is about on par with the old 3.8-litre V6 that once resided under the bonnet. At the moment the Wrangler is running the standard 79-litre fuel tank – there’s also the 40-litre AEV fuel caddy on the back if things get desperate.

Mark reckons he will fit a long-range fuel tank at some point in the future, but at the moment he can carry plenty of extra fuel on his trailer.

With its matching silver paint, black guards, Pro Comp muddies and AEV rims, Mark’s trailer almost looks as though it came out of the same Toledo factory in Ohio as his JK Wrangler, but nothing could be further from the truth. “We custom built it ourselves,” Mark says. “It runs 37-inch tyres, the same bead-lockers that are on the car, airbag suspension with four links; it runs a Front Runner roof rack… it’s pretty much just a gear trailer, not a camper.

Jeep JK V8 13“We call it the boys’ trailer; when I go away with mates we put all our camping gear in it, bike racks, kayaks, all that type of stuff.”

So what’s in the pipeline for Mark’s mighty Hemi V8 JK Wrangler? “Apart from putting a long-range tank in it, she’s almost done,” Mark says.

After a pause, though, he continues with a laugh, “I might think about supercharging the motor… you’ve got to spend your money on something!”


Engine  5.7-litre Hemi V8 (260kW/530Nm)
Transmission  Jeep/Dodge heavy-duty automatic
Transfer case  Standard
Diffs Dynatrac 44(front);Dynatrac 60(rear) with ARB Air Lockers
Suspension  AEV DualSport SC
 3.5-inch lift
 Bilstein remote reservoir dampers
 Currie Antirock front sway bar
Exterior  AEV front and rear bars AEV bonnet
 AEV wheel carrier,fuel caddy and hi-lift jack mount
 AEV corner guards
 Front Runner roof rack
 Mopar Enhanced Rock Rails
 Warn 9.5ti winch
 Redarc BCDC battery charging system
Interior  Custom drawer system
 Adventure Trailers cargo rack
 sPOD electrical system
 Hema Navigator HN6
 Icom UHF
Thanks to  Jeep Konection
 Off-Road Konection (Pro Comps)
 Dyers Auto Engineering
 Explore X 4 (Front Runner)
 Delux Kustoms (Trailer paint)

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