Daniel Armstrong’s Holden HR Special

Don’t be fooled by the classically demure exterior of Daniel Armstrong’s HR – there’s a 1000hp beast lurking within

Photographers: Mitch Hemming

Remember your first car? Daniel Armstrong certainly does, since this stunning HR Special is the very same one he bought from his grandparents almost 30 years ago – albeit with a rather serious makeover. “Nan wanted to get rid of it, but she said she’d sell it to me when I turned 16. I started saving straight away,” he says. “They bought it brand new, and I even tracked down the original number plates for it.”

First published in Street Machine’s Summer Special magazine 2023

Like many of us petrolheads, young Dan dumped his apprentice wages into upgrades like a disc front end, a hot 202 and a Supra five-speed, and wrestled the HR to a 13.9-second quarter. Eventually the car took a back seat to work and family, but in early 2021, Dan’s hankering for V8 power saw the Holden delivered to Andy and the crew at Spot On Performance & Fabrications for a serious upgrade under the skin.

Dan’s brief to Andy was pretty simple. “I wanted to be able to just get in it and drive, and I wanted to have instant power,” he says. In addition to that, Dan didn’t want any metal hanging out of the bonnet or to ruin the HR’s lines with a reverse cowl, and obviously it had to have enough mumbo to give him a thrill on the quarter.

He’d originally set his sights on a tasty 383-cube small-block and had even bought appropriate number plates to suit, but it wasn’t going to tick all the boxes. Enter Sydney-based LS guru Troy Worsley of Warspeed Industries.

Troy and the Warspeed crew built a stout LS Next mill measuring up at 427 cubic inches thanks to a Dart block, Callies stroker crank, Molnar rods and CP slugs. Sealing the cylinders is a pair of Higgins CNC-machined heads, while a knobbly Kelford cam controls the valves.

The real party-starter is the Harrop 2650 blower that shoves slightly more than an extra atmosphere down the 427’s throat, resulting in a walloping 1014hp at the hubs in full street trim and a serious headache for the Mickey Ts! Backing up the monster motor is a suitably tough Turbo 400 from Elite Automatics, with a bolt-together converter specially ordered from PTC in the States.

All that mumbo heads rearwards through a 3.5-inch Driveline Services tailshaft to the sheet-metal nine-inch, with a custom four-link keeping the tyres planted. Everything around the front and rear chassis rails has been suitably strengthened, and an extensive rollcage ties it all together.

The front underpinnings were swapped out for a Castlemaine Rod Shop rack-and-pinion IFS set-up, and Wilwood discs front and rear wash off speed with far more haste than the original instant-lane-change drums ever could.

Many builds that grace these pages start with a car that’s half rust, but Dan’s grandparents had looked after the HR extremely well. “My panel beater, Gavin, said it was one of the cleanest cars he’s ever worked on; the only rust was a 50 cent-sized spot in one quarter panel,” he says proudly. That meant the HR was a near-perfect canvas on which to lay the striking blue-and-white paint scheme.

While that colour combo may look like it’s straight out of the ’66 brochure, the blue is actually a custom mix to replicate the hue Dan and a mate had sprayed the HR way back in the good old days, while the white on the roof was simply the brightest one within reach at the time. Many of the sparkly bits, lights and the front and rear windscreens had to be replaced or refurbished to match the brand-new paintjob, although the badges are the ridgey-didge ones wearing a new lick of paint.

Of course, the interior deserved a makeover to match the rest of the car, so the HR was sent to Chris at Trim FX for a tidy-up. Chris wrapped the pews and door trims in a combination of leather and suede, highlighted with blue stitching to match the bodywork; even the headlining copped the suede treatment.

Dan drew the line at suede for the floor, though: “I wasn’t going to spend that kind of money on something the kids are going to put their feet on,” he laughs. Bliss Custom Machining knocked up a billet dash pod based on the original HR version. It houses the Holley display, but other than that, the cabin is devoid of gauges.

It goes without saying that any vehicle approaching the 1hp-per-kilo magic number is going to be a riot to pilot, and the HR is no exception. “It doesn’t hook up well on the street,” Dan laughs, “but if you get it up to speed first and don’t quite bury the foot, it really boogies.”

Although he hasn’t had a chance to pedal the HR down the 400m equaliser yet, the numbers suggest Dan might soon be taking home some eight-second timeslips without much faffing about. “As soon as Andy’s done showing it off, I’m going racing!” he says.

And there’ll be no slowing down off the track, either: Dan’s wife Lisa wants to build a nice HG cruiser that absolutely, definitely, surely won’t be overpowered!


Paint:PPG Custom
Block:427ci Dart LS Next
Supercharger:Harrop 2650
Injectors:Injector Dynamics 2000cc
Valve springs:PAC
Pistons:CP Bullet
ECU:Holley Dominator
Oil pump:Melling
Fuel pump:Triple TI Automotive 525
Converter:PTC bolt-together
Front:Viking springs and shocks
Rear:Swift springs, Gazzard Brothers shocks
Brakes:Wilwood discs with four-pot calipers (f & r)
Rims:Weld V-Series; 17×4 (f), 15×10 (r)
Rubber:Mickey Thompson; 26×6.0x17 (f), 295/55/15 (r)

Andy and the crew at Spot On Performance & Fabrications; Troy at Warspeed Industries; Gavin at Pro Spray Marine; Chris at Trim FX; Ash at Wiring & Tuning Solutions; my wife Lisa