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Nitrous 427-cube 1971 Holden HQ LS Monaro

By Kian Heagney | Photos: Ben Hosking, 03 May 2019 Features

Nitrous 427-cube 1971 Holden HQ LS Monaro

Dave Steele's Holden HQ LS Monaro might look flawless, but it's just as much a street beast as it is a show winner

THE HQ coupe is one of the greatest shapes ever to roll off Holden’s production line, with big, swooping lines and a presence on the road that is hard to top. Dave Steele has always been a Holden man, so when he got his hands on his HQ Monaro LS coupe in 2017 he always planned on giving it the five-star treatment. We doubt, however, that even he could've predicted the quality of finish that he would end up with two-and-a-half years later.

This article on Dave's HQ Monaro was first published in the April 2019 issue of Street Machine

Holden HQ MonaroLuckily for Dave, he started out with a pretty solid base for the project. It’d been owned by a family friend of his since new, and aside from a blower sitting atop the factory-fitted 350ci Chev, the car was pretty much the way she rolled off the production line in the early 70s.

“It was a really solid car and hadn’t been messed with; that’s really what attracted me to this particular coupe,” Dave says.

Read next: 1300hp blown 1974 Holden HQ sedan - KRANKY

Holden HQ MonaroBeing a mechanic by trade, it didn’t take Dave long to start stripping the car back to its bare bones in preparation for a ground-up makeover, with both the body and chassis getting sent off to be blasted and powdercoated. Interestingly, Dave bought the Boyd Coddington wheels – measuring 18x7 up front and a meaty 18x10 in the rear with some serious dish – fairly early on in the build process.

“I bought the wheels before any of the major bodywork started so I could shape the body to fit the wheels,” he explains. “The rear has been tubbed up to the rails, with the rear guards pumped a little bit to give it that meaner stance.”

Read next: Pro street big-block 1971 Holden HQ statesman

Holden HQ Monaro wheelThe Boyd Coddington wheels sport plenty of dish. Measuring 18x7 up front and 18x10 in the business end, you can certainly see why Dave modelled his car around these spinners

The metal fab goes a lot deeper than just wheel fitment, though, and it takes a keen eye to spot the hours of work that have gone into this build. The floor has been reshaped with a bigger tunnel, allowing the twin exhaust to be tucked up away from pesky speed bumps, while the ugly factory heater box on the firewall has been chucked in the bin and smoothed over. All the wiring, brake and fuel lines have been concealed from view wherever possible, making the underside of this coupe as impressive as the sleek exterior. “All the lines and wiring have been tucked and hidden, and all the Speedflow lines use aviation-grade fittings; there’s barely a hose clamp used in the car,” Dave says.

Read next: Ten-second 427ci small-block Holden HQ sedan

Holden HQ Monaro bootThe 90L fuel cell is from Rocket Industries, making sure the 472ci Chev is well-fed with go-go juice. The battery has also been moved to the boot, with just one loom running all the electrics to the MoTeC management hidden under the dash, making for a super-clean installation. While Dave hasn’t had a chance to give the nitrous system a spray yet, it added around 200hp on the engine dyno

While the car came with a 350 when it rolled off the line 40 years ago, Dave knew that he’d need a more serious donk to match the build quality. After doing some reading he opted to go with the boys at BG Engines in Sydney, landing on a Chevy Dart block that was stretched to 427ci. Damian and the boys from BG threw all the good fruit in, including a Scat crank, Callies H-beam rods and a Melling billet-drive oil pump. There’s a custom-grind BG solid cam, and a pair of AFR heads that’ve had the full CNC-porting treatment from BG in-house. Topping off the whole package is a Quick Fuel 850 carby, making the combo good for 650hp on 98 pump fuel. “Damo said it’s one of the few engines he’s ever actually wanted to keep; it’s a ripping motor,” Dave says.

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Holden HQ MonaroBacking up the donk is a Turbo 400 with an SDE 3000rpm stall converter, with a transbrake for good measure. The rear end is a really impressive unit, with a Race Products sheet-metal nine-inch housing that uses all the factory pick-up points, with a 35-spline Strange centre sporting 4.11:1 gears. A complete Wilwood disc-brake kit helps Dave keep the big beast under control, while QA1 coil-overs all ’round give it the killer stance and grip he needs. While it’s a street car, Dave built it with the intention of hitting the drag strip. “The driveline is built to handle around 1200hp, and all the set-up we did is built around drag racing,” he says. “I’ll do the show car rounds a few more times and then hit the strip and see what it can do.”

Holden HQ Monaro engine bayDamian and the boys from BG Engines churned out an incredible mill for Dave. Pushing 680hp on race fuel at 7000rpm, you better bet this thing is able to make you squeal like a little schoolgirl when you put the hammer down 

The interior is a much simpler affair, with nothing out of the ordinary bar the B&M ratchet shifter and MoTeC C125 dash. It was a case of improving on the factory offering while keeping things simple; the leather on the seats was sourced from a Bentley catalogue, while the carpet is Mercedes stuff. It might not have a/c, but thanks to the floor-to-ceiling insulation Dave put in, heat management isn’t much of a problem. “We take it out in the summer all the time. We took it to a show in 38-degree heat with the missus and my kids and they loved it,” he says. “It gets plenty of air flow and the car’s cool so we can motor all day long in the heat.”

Holden HQ Monaro interiorIf you think those seats look comfy, you’re right. Using leather nicked from a Bentley catalogue, Dave made sure he kept the original look of the Holden interior while improving it with personal touches. The carpet comes from a Mercedes, adding to the luxury LS Monaro feel

Dave gets the car out as much as he can, and reckons it’s a dream car to drive. “It looks nice, sounds tough and goes hard, which is exactly what I wanted it to do,” he says. The car’s already got a bunch of tinware to its credit, taking out the Best Show Car award at the Monaro Nationals in 2018, Best Holden at Harry’s Café De Wheels, plus a host of other awards to cram into the trophy cabinet. Dave’s hoping it’ll make an appearance at 2020’s Street Machine Summernats 33, but for now he plans on just driving his dream and enjoying it for what it is.

Holden HQ Monaro dashDespite the MoTeC dash sitting right in his face, Dave made sure all the factory GTS gauges still work with the new kit. The button panel has a few neat additions, most notably the nitrous button and the cheeky skidding-car button, which operates the transbrake 

“I just can’t stop driving it; it’s my dream car and I just can’t thank everybody enough who helped me build it so quickly,” Dave says.

SMOOTH OPERATORS

DESPITE the high level of build quality, it didn’t take the usual 10-plus years to piece together Dave’s Monaro that such builds often demand. The whole process only took around two-and-a-half years, with the car never getting stuck in limbo in between jobs. “I just kept everybody in the loop and things went really smoothly,” Dave says. “We were never waiting on an engine or any other work; it all flowed really well and I can’t thank all the guys enough for being transparent with me to get the job done.”

Holden HQ MonaroIt was an important build for Dave; 15 years ago he was involved in a car accident that had him in and out of the hospital dozens of times, and he even flatlined twice on the operating table. After that he decided that following your dreams was more important than anything else, and so his HQ Monaro project was born.

Holden HQ Monaro underside“I knew everybody who helped me with the build before it started, but now we’re all like family,” Dave says. “It was almost sad when it ended, but I feel so humbled going to all these car shows and getting the recognition and rewards it’s had.”

Dave SteeleDAVE STEELE
1971 HQ HOLDEN LS MONARO

Paint: Glasurit white

ENGINE
Brand: 427ci Dart Chevy
Induction: Edelbrock
Carby: Quick Fuel
Heads: AFR CNC-ported
Camshaft: Custom solid-roller
Rockers: Jesel
Belt Drive: Jesel
Conrods: Callies H-beam
Pistons: SRP/JE forged
Crank: Scat forged steel
Oil pump: Melling billet-drive
Fuel system: Aeromotive pump
Cooling: PWR radiator
Exhaust: 3in ceramic-coated
Ignition: ICE
Power: 650hp

TRANSMISSION
Gearbox: Turbo 400
Converter: SDE 3000rpm stall
Diff: Race Products 9in, 35-spline, 4.11:1 gears

SUSPENSION & BRAKES
Front: QA1 coil-overs
Rear: QA1 coil-overs
Brakes: Wilwood discs; 355mm (f), 310mm (r)
Master cylinder: Wilwood

WHEELS & TYRES
Rims: Boyd Coddington; 18x7 (f), 18x10 (r)
Rubber: 26x8 (f), 28x12 (r)

THANKS
Mick and Damo at BG Engines; Mick, Dave and Scottie at Street Cred Differentials & Fabrication; Bill at Hy-Tone Motor Trimming; Derrick at Clearview Windows; Justin at ProWire; Jason at Unique Restorations; Shane at Motorsport Connections; Peninsula Paints; Coastal Abrasive Blasting; my mates Gary, Glen, Peter and Phil; my dad Ralph; my partner Vanessa and my two girls Emily and Mia and everybody else who was involved