Pro touring HK Holden ute – ABADHK

Packing a 550rwhp LSX, manual 'box and a tray-load of clever tricks, Daryl O'Sullivan's HK ute defines Aussie pro touring

Photographers: Mitch Hemming

Daryl O’Sullivan didn’t mean to create an Elite-level car when he began the build on his HK ute – it just happened that way. “It was built to be driven, but these things can get out of control,” says Daryl of the handmade, all-steel, airbagged pro tourer known as ABADHK. “It was just meant to have the rust fixed, be painted and have an LS swapped in. But as we did things, it just led to the snowball effect and everything was elevated.”

First published in the February 2022 issue of Street Machine

We last saw Daryl’s HK ute (which he bought as his first car at the age of just 15), in the November 2018 issue of SM, where it was resplendent in raw metal. This allowed us to see many of the amazing yet subtle modifications done to the iconic Holden by Chris Wells and his team at BMV Engineering on Queensland’s Sunshine Coast.

To start with, a smoothed Y-frame was welded into custom narrowed chassis rails to form a full chassis, and the sills were extended through the bottom of the front guards. Other work included a welded-up tailgate; front and rear rollpans; the door quarter-glass getting the heave-ho; filled-in cowl vents; custom wheel tubs in the smoothed tray; a full sheet-metal floor; smoothed engine bay; and a bespoke fuel tank and filler packed under a door in the custom tray floor.

Welding the front end to the rest of the car to form a solid monocoque was partly for aesthetics but also for a solid engineering platform, given Daryl’s desire to rack up plenty of road miles with an angry LSX V8 up front.

“We decided the front wasn’t going to come off again, and it was going to make the ute a lot more rigid,” Daryl explains. “Once we had cut the floor out of it, I figured we may as well keep going. Plus, the stock subframe is ugly, so Chris and I figured we may as well smooth it out, as it would all fit better with the other smoothed edges and painted panels.”

With the original goal of a neat cruiser long gone, Daryl and Chris worked towards a far more adventurous vision. “The plan Chris and I came up with was to have a new car wrapped in an old shell, so it was going to have all the mod cons: air con, power windows, central locking, power steering, an LS, and it was also going to be manual,” Daryl says.

Since that 2018 feature, there has been plenty of action to get the ute ready to have the covers whipped off it at Rockynats 2021, which it did to great success. However, the build was interrupted for a while by life getting in the way.

“Following the previous photoshoot, I took the ute home to Mackay for 12 months and basically forgot about it, because I was so busy with work,” Daryl laughs.

Nonetheless, he was able to pull the 376-cube GM Performance LSX crate motor out of the bay and send it to Jamie Swift of Swifty’s Race Engines. The Drag Challenge veteran then added a custom cam of secret specs and had Nathan Higgins put a CNC port job through the six-bolt LSX heads, before a Plazmaman billet intake manifold was given the nod.

Running through a late-model GM E38 Siemens ECU and putting the power down through a six-speed Tremec manual ’box, the HK has pulled 550rwhp on the dyno at Auspeed Tuning in Mackay. “It is definitely lumpy now, and it shakes a fair bit at idle,” laughs Daryl.

While it was great he got the angry LS sorted, Daryl still needed to get the ute painted. He initially had the sweet eye for Mazda’s Soul Red hue, but discussions with painter Callum Conway led to test panels being sprayed out using House of Kolor’s awesome Brandywine candy red.

“Callum mentioned the Mazda red can be really difficult to colour-match if you need to blow it in, and the Brandywine won’t be any easier, but then we test-sprayed the House of Kolor on a grey base and a black base and it was so easy to see that the Brandywine was the way to go,” Daryl says.

With that decision made, the HK was delivered back to BMV, where it was blown apart so that Callum could then get busy with the spray gun.

While painting a car is normally a 30-second montage on TV, in real life it’s no overnight job. “Callum has a day job, so he was only able to chip away at painting it after hours and on weekends, so it took a while to come together,” Daryl says.

“The large parts of the reassembly then happened quickly, but it is all the little details that take ages. We got it finished and put it straight in the trailer to take it to Rockynats, so we didn’t get any time to shake it down before then.”

The good news is that, having built the ute into a functional car back when it was in bare metal, there were few surprises for the team. “Doing the dry fit-up saved massive amounts of headaches, as we could find all the problems with the running and driving car before doing it for the final time,” Daryl says. “It turned out 1000 times better than I ever thought it would. It gets driven every week, so I’d call it a pro tourer. And it drives beautifully.”

Sounds like it drives as well as it looks!


The GM Performance LSX range of crate motors are a decent spot spicier than the production engines sharing the LS family tree. Formerly available in a range of capacities from 376ci (6.2L) up to 454ci (7.4L), these iron-block motors serve as off-the-shelf factory upgrades for hot streeters and race cars.

The 476hp LSX376-B8 is the little brother to the LSX376-B15, both of which are boost-rated (9.0:1 comp ratio) variants of the LS3. The B8 is rated by GM for a conservative 8psi of boosted air, while the B15 can take up to 15psi. Both engines run a hydraulic-roller cam (204/211-degree for the B8 and 210/230-degree for the B15), roller trunnion-equipped rockers and LS3-pattern cylinder heads. However, the B15 packs a forged crank, rods and pistons, whereas the B8 uses a nodular-iron crank and powdered-metal rods.

The big dawg of the range is the LSX454, which used to be offered in two guises, both with a 4.185in by 4.125in bore/stroke in an iron block, and topped with deep-breathing, six-bolt LS7-format alloy heads.

The standard LSX454 rocks a 236/246-degree cam, 4340 forged steel crank, forged slugs and rods, 11.0:1 comp, titanium intake valves and lightweight sodium exhaust valves. It is rated to 627hp, but is the same physical size as any other LS engine.

Discontinued as of July 2018, the 750hp LSX454R was really a race engine, boasting 13.1:1 comp, a solid-roller valvetrain, eight-bolt forged steel crank, 1.9-ratio rockers, 1150cfm Holley Dominator-pattern throttlebody and a high-riser single-plane intake manifold.

Want big boost-ready power with a warranty? Have a look at the LSX options.


Paint: House of Kolor Brandywine
Brand: GM LSX376
Intake: Plazmaman LS7
Heads: Higgins CNC-ported six-bolt LSX
Cam: Custom hydraulic-roller
ECU: GM Siemens E38
Fuel system: 550cc injectors, Aeromotive pump, custom tank
Oil system: Holley retro-fit sump, Melling oil pump
Cooling: Aussie Desert Cooler Burnout King radiator
Exhaust: Custom 2in extractors, twin 3in system, MagnaFlow mufflers
Gearbox: Tremec T56 Magnum six-speed manual
Clutch: Direct Clutch Services twin-plate
Diff: Strange Engineering 9in, Strange 35-spline full-floater axles, Strange
3.7:1 final drive
Front: Slam Specialties bellows airbag, QA1 shocks, custom front end, tube front
control arms, steering rack conversion, Billet Works steering column, Y-frame
modified and welded to the body
Rear: ShockWave air struts, tubbed rear, custom rear chassis rails, McDonald
Brothers triangulated four-link, AccuAir e-Level height management
Brakes: Wilwood four-piston calipers and discs (f & r)
Master cylinder: Wilwood
Rims: Weld Racing V-Series; 17×4.5 (f), 15×12 (r)
Rubber: M/T Sportsman SR; 26×3.00R17LT (f), 26×12.00R15LT (r)


Chris, Craig and Jesse at BMV Engineering; Cam at North Coast Custom Trim for knocking out the killer trim; Callum Conway for all the time and hours in the body and paint – it speaks for itself; Rodger at Ol’ Skool Electrics; Jamie Swift at Swifty’s Race Engines; my parents for helping with everything and storing the ute for all those years; my missus Ashleigh for all the trips to Brisbane for the car and all the help at the car shows