8-second Holden HJ Monaro GTS

Jeremy Tomic’s HJ Monaro went from barn-find to 1100hp street brawler

Photographers: Chris Thorogood

IT’S the stuff red-blooded enthusiasts like you and I dream of: the doors of a shipping container swing open and there sits a perfectly preserved time capsule of automotive excellence that last saw the light of day at Summernats ’96.

First published in the December 2021 issue of Street Machine

That’s exactly how Jeremy Tomic first laid eyes on this HJ a few years ago – a genuine Monaro, no less! “The boys had painted it Maranello Red from the VH Commodore and put a big-block in it for the ’Nats, then stored it away. It still had its entrant stickers on when I dug it out of the container!” Jeremy recalls. “My dream was always to own an HQ, but after we gave this thing a quick wash, we did a deal then and there. The only condition was that if I ever sell it, the previous owner, Jason, gets the first chance to buy it back!”

Jeremy initially wanted to build a nitrous big-block for it. However, with his long-time friend and Street Machine Drag Challenge regular Mark Drew pitching in, the pair put their heads together and decided to go a different route, building the car entirely during Victoria’s lengthy 2020 COVID lockdown.

“I wanted a proper street car; it had to be all engineered,” says Jeremy, which was one of the deciding factors that secured the HJ’s LS-powered fate. Drawing plenty of inspiration from Kai McPhee’s stomping, seven-second, 5.3-litre turbo LS VC Commodore that Drewy also built the engine for, Jeremy sourced himself a 5.3 block and left Mark to work his magic.

The 362-cube bottom end is a fairly straightforward affair, with a Callies crank slugging Molnar rods and CP forged pistons into the bores. A set of CNC-ported Higgins heads seals the long motor up, with a custom intake manifold perched between them.

“I originally wanted a mild nine-second combo, but Drewy was never just going to let it be mild!” laughs Jeremy – hence the GTX55 turbo hanging from custom exhaust manifolds. “We made 1130hp on this combo using log manifolds, but I’ve since made a set of four-into-ones for it and it’s made a massive difference,” explains Mark of the turbo set-up.

“The turbo is so big that it actually makes it nicer to drive on the street,” Jeremy adds. That’s not to say that the boys don’t have a few tricks up their sleeve to wake the snail up when it’s time to race, though. “The converter is around 3800rpm, and there are a few little secrets in there that we don’t want to give away,” Drewy says.

Jeremy’s HJ is governed by a Holley EFI engine management system, with West Aussie Jeff Johnson in charge of the tune. “We picked up the Terminator X and a few extra sensors, and my good buddy wired it all up,” Jeremy explains. This included mounting and setting up the CO2 system, which helps the crew manage boost.

Keep in mind that the HJ is Jeremy’s first serious street machine. So how did he adjust to racing it? “When we did the suspension set-up with Shane from Marshall Speed Shop, I just told him that I needed the car to go straight, and he delivered,” he says. Amazingly, the underpinnings of the HJ are incredibly simple, with King springs and Viking shocks up front and an all-Viking affair in the rear end, coupled with an anti-roll bar. “The next step for Jeremy would be a much bigger investment in the suspension, but the Viking stuff is working for now and it’s pretty good value,” Mark Drew says.

The HJ made its maiden pass at the 2021 Holden Nationals, and by the time the event was over it had reeled off an 8.83@152mph. “I hit the limiter and was off the throttle eight seconds into that run,” Jeremy says. The boys hustled to fix a few teething issues in the pits and sneak one more run in, but the delicate juggling act of a sticky Heathcote track, 275 drag radials and over 1100hp laid waste to the HJ’s diff, and their day’s racing.

The diff has been substantially beefed up since then, with 35-spline billet axles, 3.25:1 gears and a full spool tucked inside a nine-inch housing. “I’d really like to get a high seven out of it, but there’s no ’cage in it yet,” says Jeremy. With Drewy’s new manifolds liberating a good amount of extra horsepower, we reckon that’s just a matter of time.


Paint: Maranello Red
Brand: GM 5.3L LS1
Induction: Custom intake manifold, Jonny Tig front-mount intercooler, GTX55 turbo
Heads: GM castings, CNC-ported by Higgins 
Camshaft: LJMS Stage 2 hydraulic-roller
Conrods: Molnar 
Pistons: CP forged, 9.7:1 compression
Crank: Callies 8-counterweight
Oil pump: Melling 
Fuel system: Three Walbro 525 fuel pumps, Bosch 1650cc injectors
Cooling: Race Radiators alloy radiator, twin SPAL fans
Exhaust: Custom turbo manifolds, 4in stainless system, MagnaFlow muffler
Ignition: LS3 coils, MSD leads
Gearbox: Turbo 400, transbrake
Converter: Custom Dominator 3800rpm
Diff: 9in housing, 3.25:1 gears, 35-spline billet axles, full spool
Front: King Springs, Viking shocks
Rear: Viking springs and shocks, anti-roll bar
Brakes: Wilwood discs (f & r) 
Master cylinder: Wilwood
Rims: Weld V-Series Pro 15×3.5 (f), Weld V-Series Pro with beadlock 15×9
Rubber: Moroso front-runners (f), Mickey Thompson ET Street SS 275/60R15 (r)

Mark Drew for all his input throughout the build; Uncle Ricca and Mick at Race Parts Melbourne; Dandy Engines; Kavanagh Auto Parts; Jason at Dominator Torque Converters; Aikman Engineering for the diff; Jeff Johnson at Streetbuilt Racing; Shane at Marshall Speed Shop; Timmy for his help with the brakes and tuning at the track; Admir for wiring the car; Sami at Proclass Detailing; Sammy and Timmy at CNC Pro; Regan Leslie; Steve; Timmy; Shaneo; Kai ‘The Creswick Sausage’; Lumper; Tahnee