EIGHT-SECOND 850RWHP CRUSTY HZ KINGSWOOD

HZ Kingswood turbo LS 12 nw

RAT ROD, patina, barn-find. Few words in the car lovers’ vernacular have been abused and cheapened more than these three. So it’s a relief – no, a Christmas miracle – to come across a fresh and legitimate application for at least one of these terms: patina.

This story on Jesse Boothroyd's crusty Kingswood was originally published in the April 2017 issue of Street Machine magazine

“Nice panel and paint won’t make it go quicker,” says Geelong’s Jesse Boothroyd, owner and builder of this deceptively crusty-looking eight-second HZ Kingswood. “People are always asking when I’m going to respray it, but it looks bad-arse as-is, and I think the money is better spent on making it faster.”

You can’t argue with that logic, and let’s face it, Jesse’s HZ has its own identity now – adding fresh paint to its nicely ruffled exterior would ironically take the ‘shine’ off its presence both on the street and the strip.

The Kinger came into Jesse’s life as a grandpa-spec survivor running a 202, three-on-the-tree manual and a blown banjo diff – the latter thanks to Jesse when the car was owned by his friend Josh. “There’s nothing wrong with doing a skid in your mate’s car!” he laughs. “I thought I’d see if it could do a burnout. I got it spinning in first, flat-changed the column-shift into second and bang – it was all over.”

Josh sold it to another of their mates, Lee, who palmed it off to their friend Jake, until finally becoming Jesse’s a few years ago. “It did the rounds but nobody really wanted it,” he says. “It was cool and all, but wasn’t a mint car, nor was it an HQ, and for me it was an impulse buy. I was building a VS Commodore at the time with a turbo LS, but that project was dragging on so I thought: ‘Stuff it. Let’s chuck all the running gear into the HZ and get it on the road.’ No tubs, no rebuild, just a quick turbo swap into a dirty old Kingswood.

“Of course, that plan went mostly out the window!” he laughs. The 403-cube LS donk was expertly built by Tim Holmyard at TJH Performance in Geelong. It’s cranked out 850hp at the treads and has pushed the heavyweight HZ to an 8.94@153mph best on 17lb of boost.

Tim chose an LQ9 6.0-litre cast-iron truck block, filling it with a Callies Compstar stroker crank and rod assembly topped with CP Bullet pistons. A TJH-spec custom hydraulic-roller camshaft rounds out the short assembly, while Higgins CNC-ported L98 heads were chosen to house stainless valves with titanium retainers, Comp trunnion rockers and PAC valve springs.

A custom Proflow intake manifold was modified by Mark Drew and mounts Bosch 1650cc injectors and Holley fuel rails to correctly disperse the E85, while a 92mm Aeroflow billet aluminium throttlebody controls the air intake following a detour via a hefty front-mounted intercooler. The brains of the operation is a Haltech 2500 Elite ECU that works in conjunction with a Haltech/Racepak digital dash and sensors for just about everything.

A whopping single Garrett GTX4508R turbo and 60mm Precision wastegate make the LQ9 get up and boogie, nestled into the HZ’s bay with HPC-coated 1.75-inch steampipe exhaust manifolds, with a five-inch dump pipe channelling into a twin three-inch exhaust system. Cooling is provided by an eBay-spec alloy radiator and twin thermo fans from a Ford Mondeo (the latter surprised me; I was sure Mondeos had nothing positive to offer), while a brace of chassis-mounted LS3 coil-packs light the fire.

An FTI Level 5, full-roller, Reid-cased transbraked Powerglide transmission might be a mouthful, but that’s what happens with a 2000hp rating. It’s fronted by a TCE 3200 converter and Meziere billet flexplate. An A1 3.5-inch tailshaft with Strange yokes offers a similar horsepower rating and was supplied by DTM Transmissions in Geelong. Out back, an Aikman Engineering braced sheet-metal nine-inch housing is filled with a Strange nodular centre and alloy pinion support, and a full spool mounts 3.25 gears and locates 35-spline axles.

The front end pretty much remains Holden’s catchcry Radial Tuned Suspension, apart from bolt-in Viking double adjustable coil-over shock assemblies, while the rear uses same-brand coil-overs with adjustable Pro9 upper and lower control arms. Factory HZ disc and drum brakes remain, albeit fully rebuilt with the inclusion of slotted rotors, and activated by a Wilwood master cylinder.

Jesse earns a crust as a boilermaker and steel fabricator, so was more than qualified to notch the rear rails and modify the boot floor for diff housing clearance, while mini-tubs were necessary to house larger Mickey Thompson 275/60 Radial Pro meats on 15x9 Weld AlumaStar beadlock rims. Billet Specialties 15x5 Street Lites support the front end and run Nankang 185/65s for good measure.

The interior has been retrimmed in black along factory lines by Bec Lloyd, with a Billet Specialties wheel and TCI Outlaw shifter replacing the old boiled-egg HZ twirler and column assembly. The rollcage is extensive and is again more evidence of Jesse’s fabrication skills, along with the help of good mate Jake Bradley. “Jake and I built and welded the entire ’cage, which includes removable intrusion bars, underfloor and underdash bars and a parachute mount,” Jesse says. “I was fussy on fitment too, as I’m a tall bastard so I needed it to be comfortable for both the street and the strip.”

As you may have noticed, the Atlantis Blue exterior remains as-bought with 40 years of weathering left intact. The firewall was flattened and the inner guards smoothed to add some bling, before being painted by close mates Luke Foley and Brendan Cherry. Neither are strangers to the pages of SM as stalwarts of Drag Challenge and owners of a turbo LS-powered VH Commodore and HK Monaro respectively. They played more of a role in Jesse’s build than they probably realised: “I watched a lot of my friends like Luke and Brendan breaking stuff and finding the limits with certain parts; their guidance made it easier to build mine and do it properly first time ’round,” Jesse says. “I ended up buying then selling quite a few parts before they were even fitted, and learning from their experiences has no doubt saved me many headaches.”

That’s not to say the HZ project was all sunshine and lollipops, but Jesse had a great team of friends supporting him in the lead-up to Street Machine Drag Challenge 2016 and during the event itself. “I went as crew for Luke back in 2015 and I knew immediately what the HZ was being built for. I entered for 2016 but had been terribly sick leading up to event and off work for nearly three months. My mate Ryan Schmock put up the coin for the entry, and he and my wife Daniela kept me on track and gave me so much help to get the car ready in time. Adam Rogash and Luke Foley from MPW Performance tune the car, and although I do the spanner work myself, they are only ever a phone call away if I need advice.”

Jesse made it to Drag Challenge only to find he was struggling to get traction. Crappy weather leading up to the event put a kibosh on any thorough testing, and the best he could manage in the early stages of DC was 9.20s.

“It kept blazing the tyres, which was totally out of character,” he says. “By the end of Day Three it was getting frustrating so I went and spoke with Kyle Hopf from 6boost who was crewing for Terry Seng and explained the situation. He knew just by looking at it – I’d raised the back end to tow the trailer and Kyle was adamant that I drop it back down and try again. Sure enough, it went 8.98@151mph on Day Four at Swan Hill. I just wish I’d spoken to Kyle on the first day!”

Jesse’s only real plan for the HZ is a return to Calder, where he hopes to run an eight. “It’s my home track,” he says. “The planets haven’t aligned yet for me there but I really want that Calder timeslip with an eight-second pass. Then I’ll probably build something new, maybe another VN-VS Commodore. The HZ tips the scales at 4000lb, so I need something lighter. I love this old girl, but I want to go quicker so it’s time to start looking at other options.” 

JESSE BOOTHROYD
1979 HZ HOLDEN KINGSWOOD
Colour: Atlantis Blue

DONK
Engine: Chevrolet 403ci
Block: LQ9 6.0L
Turbo: Garrett GTX4508R
Intake: Proflow custom modified
Throttlebody: 92mm Aeroflow billet aluminium
Heads: Higgins CNC-ported L98
Crank & rods: Callies Compstar
Pistons: CP Bullet
Cam: TJH custom hydraulic-roller
ECU: Haltech 2500 Elite
Ignition: 8 x LS3 coils
Exhaust: Custom 4-into-1 headers, twin 3in system

SHIFT
Transmission: FTI Powerglide
Converter: TCE 3500 stall
Tailshaft: A1 3.5in, Strange yokes
Diff: Fabricated 9in, Strange centre, full spool, 3.25 gears

BENEATH
Suspension: Viking coil-over shocks (f & r); Pro9 adjustable control arms (r)
Brakes: Wilwood master cylinder, HZ slotted discs and Girlock calipers (f), stock drums (r)

ROLLING STOCK
Rims: Billet Specialties Street Lite 15x5 (f), Weld AlumaStar beadlock 15x9 (r)
Tyres: Nankang 185/65 (f), M/T 275x60/15 Radial Pro (r)

THANKS
My wife Daniela and best mate Ryan Schmock for putting up with all the late nights and keeping me motivated; Luke Foley & Adam Rogash, MPW; Brendan Cherry, Pro Layers Bodyworks; Craig & Aaron, DTM Performance Transmissions; Antony Jakovac; Tim Holmyard, TJH Performance; Jake Bradley; Rade Mitrovic; Tony Gilberti; Adam Pollard; Daniel Zane, SPCALK Custom Detailing; Shane Stretton, SS Polishing; Robby Abbott; Chris Spencer, SRE; Nathan & Scott, Exhaust Builders Geelong

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