Holden HK-HG Monaro V8 - Buyer's Guide

By: Cliff Chambers

Date: 27.01.2023

Holden's response to the Falcon GT became an instant classic and a Bathurst winner

Australians during the 1960s acquired a taste for glamorous cars but didn’t have one of their own until 1968 when Holden introduced the Monaro.

It was based on the HK sedan, which in January of that year brought a handsome change to the Holden range with its flared wheel arches, ‘hipped’ rear quarters and plenty of glass.

Monaros, like other models in the HK range, could be bought with six-cylinder engines and column shift transmission, but rumbling V8s and four-speed transmission were the enthusiast preferences.

‘Bathurst Spec’ Monaros used a 5.3-litre, 327 cubic inch engine that wasn’t available in any other kind of Holden. For mainstream drivers though, there was a 307 cubic inch version with manual or two-speed Powerglide transmission.

| Market Review: Holden HK-HG Kingswood/Premier/Brougham/Monaro

Cost containment and the need to maximise Australian content saw the imported V8 replaced during the reign of the HT model by 4.2 and 5.0-litre versions of a new, all-Australian engine.

Passenger safety was important too, with the Monaro dash sloping dramatically away from occupants’ knees. Along the top ran crash padding, there was a collapsible steering column and three-point seat belts. GTS V8 Monaros had dual-circuit brakes with front discs. Tyres were cross-ply, rated to 125mph (202km/h), but with the exception of dedicated show cars, Monaros today will invariably have radials.

| Read next: Holden HK Monaro GTS 327

Other GTS features included front bucket seats, a sports steering wheel, limited-slip differential, tachometer and heater/demister. Among the options were power steering and under-dash air-conditioning.

HT models differed only marginally from the HK but did debut the first plastic grille fitted to a Holden, plus two-tier tail-lamp clusters with indicators that could be seen from side-on. Gone too was the restrictive strip speedometer, replaced by round dials in a revised instrument cluster that moved the tacho from the centre console to the dash.

| Read next: 50 years of Monaro - Holden HK

Big news for buyers of the HG models was the introduction of Trimatic automatic transmission. Australian-made and with three ratios, the new transmission helped GM-H further contain costs and maximise local content.

Understeer was the HK-HG’s dominant handling trait and was exacerbated by a V8 engine’s extra weight. Learn the techniques needed to minimise understeer though and the big coupe could be hustled along very effectively, as proved by the third-place finish recorded by a GTS350 in the 1970 Ampol Round Australia Trial.

| First Gen Monaro: HK, HG, HT

Modified Monaros are common and buyers do need to show caution. Back when HK-HG two-doors were a tenth of their current values, it didn’t matter much that a replacement motor might have come from a 1976 Kingswood. Today it does.

Any kind of alteration, including non-authentic paint and velour retrims, will hurt values, but not to the same extent as changes that give rise to compliance issues. Ensure that body or mechanical mods, even those undertaken decades ago, have been approved and ask to see engineering reports covering any significant changes.

Value Range: Monaro (HT-HG 308)

Fair: $50,000
Good: $110,000
Excellent: $165,000
(Note: exceptional cars will demand more)

BUYER'S CHECKLIST

Body & chassis

Many HK-HG models failed to survive the 1980s because a rust trap in the rear quarter panels made them uneconomical to repair. Cars that were restored will have been running for decades with replacement sheet metal and suspect rust-proofing and need professional checks to confirm that the rust isn’t coming back. Look at the quarters and rear pillars, the floors, sills, lower mudguards, wheel arches, rear spring mounting points, window surrounds and doors. Front panels are shared with other HK-HGs and are available. Bumpers are as well but you can pay $1200 each for reconditioned bars or around $600 for reproductions. Original metallic paintwork wasn’t durable and fades more quickly than solid colours.

Engine & transmission

Here comes the good news. The local or imported V8 engines fitted to these cars are immensely durable and easy to recondition. Rear main bearing seal leaks are common and rarely serious, while light rattles signify a worn timing chain. Exhaust smoke, accompanied by deeper rumblings, denotes an engine in need of a rebuild. Cars with engines that weren’t in there when the car was built – especially six-cylinders that have been upgraded to V8s – are worth significantly less than those that are totally genuine. Two and three-speed automatic transmissions typically last more than 200,000 kilometres and can be cheaply reconditioned or replaced.

Suspension & brakes

More simplicity here and everything needed to restore a worn Monaro suspension remains available. Front coil springs cost $200-300 per pair but you will pay more than double that for sets of new rear leaf springs. The steering was heavy and vague even when new, but more than 50mm of slop at the top of the steering wheel is too much. Sets of new ball joints cost less than $150 and rebushing kits around $100. ‘Bounce’ test the front and rear shock absorbers to see if replacement is due. Those used to all-disc braking systems may find the disc/drums feel strange but a very hard pedal or almost none at all indicates a hydraulic leak, booster failure or seized rear drums.

Interior & electrics

If you’re keen to maintain the car’s authenticity then interior condition is vital. Original seats with their ‘houndstooth’ inserts are highly prized but replacement covers and cloth in the correct pattern are available. Reproduction GTS steering wheels cost $650 and a real one might be four times that price. Even the nifty rear pillar interior lights are being remade and cost $100 each. Virtually everything to maintain the Monaro’s electrical system is available second-hand or from specialist suppliers; alternators for local V8s cost less than $250, those to fit Chevrolet engines are slightly dearer.

1968 - 1971 Holden HK-HG Monaro V8 specs

NUMBER BUILT: 29,529 (all HK-HG Monaro)
BODY: All steel
two-door coupe
ENGINE: 4142cc, 5030 or 5047cc V8 with overhead valves and single downdraft carburettor
TRANSMISSION: Four-speed manual, two or three-speed automatic
POWER & TORQUE: 179kW @ 4800rpm, 425Nm @ 3000rpm
(HT 308 V8),
PERFORMANCE: 0-96km/h seconds, 0-400m seconds
(HT 308 V8)
SUSPENSION: independent with wishbones and coil springs, shock absorbers & anti-roll bar (f).
live axle with semi-elliptic springs & shock absorbers (r)
BRAKES: Disc (f) drum (r), power assisted
TYRES: DR70 H14 crossply, 185H14 radial

From Unique Cars #473, Dec 2022/Jan 2023

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