Guide: Aston Martin V8 V540
Background
Having saved Aston Martin and Lagonda from oblivion during the late 1940s, British industrialist, David Brown, put the reformed company (Aston Martin Lagonda Ltd.) up for sale in late 1971.
Although the firm had not been profitable for several years and was at the time frozen out of the important US market on safety and emissions grounds, a new buyer was found in January 1972.
The purchaser was Company Developments which had a diverse portfolio of investments, but no prior experience of car manufacturing.
With the takeover complete, in April 1972 Aston Martin launched the simply titled V8 which was a facelifted version of the outgoing DBS V8.
The Aston Martin V8 was joined by the visually similar Aston Martin Vantage which used the same revamped body but with the old six cylinder engine.
As per the DBS V8, the facelifted V8 incorporated an engine with state-of-the-art Bosch mechanical fuel-injection. However, because the Bosch injection system proved troublesome, from August 1973 it was replaced with four Weber carburettors. In the short-term, carburettors made it easier for Aston Martin to meet ever-tightening emissions legislation.
Although trading conditions were tough, Aston Martin nevertheless managed to sell a respectable 288 examples of the fuel-injected V8 between April 1972 and August 1973.
Unfortunately though, over the next couple of years, the economic gloom that enveloped most major economies during the early 1970s worsened as geopolitical instability brought about an existential crisis that left many high end auto manufacturers fighting for their lives.
Engine / Gearbox
By far the most significant switch on these revised V8s was the conversion to four downdraught Weber 42 DCNF carburettors instead of the old Bosch fuel-injection system.
Importantly, the reconfigured engine was notably smoother at low revs. It was identifiable on account of silver instead of black cam covers and a new airbox.
The power rating was revised down to 310bhp at 6000rpm compared to 320bhp at 5800rpm for the fuel-injected motor. The torque rating was also slightly inferior with 320lb-ft at 6000rpm as opposed to 360lb-ft at 4500rpm. However, performance was little changed.
As usual, the engine itself was an all-alloy 90° V8 with dual overhead camshafts and two valves per cylinder. It once again displaced 5340cc thanks to a bore and stroke of 100mm and 85mm respectively.
A 9.0:1 compression ratio was retained together with Lucus OPUS electronic ignition.
Two gearbox options were offered: a ZF five-speed manual or Chrysler Torqueflite three-speed automatic.
Chassis
In addition to the switch from fuel-injection to carburettors, Aston Martin ushered in a number of other mechanical upgrades.
Improvements were made to the water and oil cooling systems. Transmission cooling for automatic variants was also enhanced.
A new fuel tank (once again located above the rear axle) meant there was more luggage space in the trunk. The fuel surge tank was deleted.
To reduce noise, new front bulkhead and under-hood insulation was fitted.
Lastly, subtly restyled GKN alloy wheels with a smooth rim and no beading were fitted. As before, the wheel rims measured 15 x 7-inches all round.
Otherwise, the specification was left alone.
The V8’s steel platform chassis had a 2610mm wheelbase. It incorporated independent double wishbone suspension at the front with a De Dion rear axle located by parallel trailing arms and a Watts linkage. Coil sprung Armstrong shocks were fitted all round along with a front anti-roll bar.
Dual circuit servo-assisted Girling ventilated discs brakes measured 10.75-inches at the front while the inboard rears were 10.38-inches.
Speed-sensitive power-assisted steering was standard.
Bodywork
To increase airflow to the new airbox, a bigger hood scoop was fitted.
The other change related to more efficient extraction of stale air from the cockpit; earlier cars had extractor ventilation louvres cut from beneath the rear windscreen while this latest variant had a shallow lip ahead of the leading edge of the bootlid which allowed air to escape.
Otherwise, the aluminium body panels were unmodified. At this stage, the V8 was offered only as a Coupe.
Interior
Inside, the front seats and door panels were subtly redesigned.
A reconfigured centre console featured revised horizontal instead of vertical switchgear, a bigger ashtray and a new cigar lighter. There was also a new rotary dial on the outer side of the dash to activate the lights. The wiper control was relocated to a stalk on the steering column.
For added practicality, the passenger door could now be locked and unlocked via a switch on the driver’s door.
The rest of the cockpit equipment was largely unchanged.
Directly behind the leather covered three spoke wheel were large gauges for engine and road speed with a small oil temperature dial in between. Off to either side were more small read outs for oil pressure, water temperature, fuel and battery condition.
A clock was housed in a central cowl between the electric window switches. Underneath were the ventilation controls and audio system.
The dash fascia and the centre console were either upholstered in black leather to match the rest of the dash or occasionally fitted with burr walnut inserts.
Air-conditioning was standard along with full leather upholstery.
Options
Optional extras included an electric sunroof, fog lights, bumper overriders, a choice of alternative rear axle ratios, fabric upholstery and various audio systems.
Weight / Performance
Compared to the outgoing fuel-injected variant, this latest V8 weighed in 13kg heavier (1740kg).
Top speed dropped from 162mph to 155mph. Cars equipped with a manual transmission could hit 62mph in 6 seconds while the auto variant took 7.1 seconds.
Oil Crisis
In October 1973, Aston Martin and most other builders of large-engined gas guzzlers were thrown into disarray when the Oil Crisis hit.
The saga began when Arab OPEC members announced an embargo on oil sales to the USA, UK, Canada, Japan and the Netherlands in response to the USA's support for Israel in the Yom Kippur War. Egypt and Syria (with the support of other Arab nations) had begun a military campaign to regain Arab territories lost during the 1967 Six Day War (when Egypt, Syria and Jordan had been the aggressors).
Oil prices rose exponentially and remained at elevated levels for the next two years.
Sales of high end motor cars plummeted overnight.
USA Version
Having been locked out of the lucrative US market for several years, one of Company Developments’ plans for Aston Martin was a return to North America with a suitably modified clean-running engine.
In October 1974, Weber and Aston finished working on a catalytic converter system that would enable the V8 to comply with US regulations for 1975.
These early emissions-equipped engines were able to run lead-free fuel and came with a belt driven air-pump that forced clean air into the exhaust system. The compression ratio was reduced from 9.0:1 to 8.3:1.
Power output dropped from 310bhp to around 270bhp.
Aston Martin Lagonda Ltd. Goes into Receivership
Unfortunately, the arrival of the Federal-spec. US engine came too late.
On December 31st 1974, with Company Developments suffering across their portfolio, loss-making Aston Martin Lagonda was placed into administration.
Production at the Newport Pagnell factory stopped although the still profitable Customer Service Department remained open.
New Owners
In June 1975, Aston Martin Lagonda’s administrators accepted an offer from a multinational consortium headed by American, Peter Sprague, and Canadian, George Minden. Both were long-standing Aston Martin Owners Club members. Soon after the deal was rubber stamped, Sprague and Minden were joined by Brits, Alan Curtis and Denis Flather.
Re-establishing the company’s affairs took some time, but the new consortium were in a position to start production again a few months later.
Importantly, the ambitious new owners sanctioned the development of three new models to join the existing V8. An exciting wedge-styled four-door Lagonda was given the green light along with an open top V8 Volante and the flagship supercar-rivalling V8 Vantage (which would initially only be available as a Fixed Head).
Relaunch
The standard V8 Coupe was available from the outset and, thanks to ongoing work behind the scenes, a US-market variant finally made it into production.
These cars came with air pumps, two catalytic converters and special 5mph impact bumpers. Power output was initially 288bhp.
In June 1977, a more powerful Stage 1 Emissions Equipped engine was introduced that featured new camshafts and a trick exhaust that boosted power to 305bhp.
V8 Volante
At the London Motor Show in October 1976, Aston Martin rocked the motoring world when they unveiled the futuristic four door Lagonda prototype. Production finally began in late 1978, by which time Aston Martin had introduced the V8 Vantage (February 1977) and the V8 Volante (June 1978).
The handsome new V8 Volante came equipped with an electric canvas roof and plastic rear window. A tonneau was supplied to cover the hood when lowered.
To incorporate the folding roof, space in the back of the cabin and in the trunk was slightly reduced.
Another feature of the V8 Volante was an additional 68kg of body reinforcements to reduce flex. Extra box sections were added to the sills and the A-pillars were also beefed up.
Cosmetically, the V8 Volante featured a sleek new closed instead of open power bulge on the hood. Inside, a full-width burr walnut dash fascia and door caps were fitted as standard along with head rests. There was also a subtly reconfigured centre console.
Under the skin, the shock absorber settings were adjusted to reflect the additional weight.
Unsurprisingly, the V8 Volante proved a major success for Aston Martin. It was extremely popular in the USA where the majority of early production cars headed.
V8 Oscar India
With the Lagonda, V8 Vantage and V8 Volante all in production, Aston Martin introduced an updated V8 Coupe at the Birmingham Motor Show in October 1978.
Dubbed Oscar India (or October Introduction), the revised variant was brought into line with the V8 Volante thanks to a closed power bulge, head rests, a reconfigured centre console plus burr walnut for the dash and door caps. The headliner was switched from cloth to leather.
A new feature unique to the revamped Coupe was a discrete rear spoiler.
As per the V8 Volante, different shock absorber settings were adopted.
Both body styles now came with an improved air-conditioning system and a new Pioneer cassette player. They could also be specified with Vantage-style Cibie spot lights housed within the front grille.
End of Production
In March 1980, Aston Martin switched over to the revised V580 engine.
The V580 power unit came with bigger valves, uprated camshafts, revised porting and pistons and a higher compression ratio. It enabled Aston Martin to offer a common basic specification throughout the entire V8 range and meant it was only a matter of selecting the appropriate camshafts and carburettors to make a V8, Lagonda or Vantage engine.
Between August 1973 and October 1978, Aston Martin completed 970 V8 Coupes of which 576 were right-hand drive and 394 were left-hand drive.
We are currently seeking precise production numbers for V8 Volantes built between June 1978 and March 1980 and V8 Coupes built between October 1978 and March 1980.
Text copyright: Supercar Nostalgia
Photo copyright: Aston Martin - https://www.astonmartin.com & unattributed
