Brit and Italian twin cam beauties – MGA vs Alfa Romeo Giulietta

| 16 Dec 2013

Bouncing along a country lane, upright wheel close to your chest, hair assaulted by the wind and with a couple of curvaceous wing-tops to aim at every apex. This could only be a traditional British sports car. 

But wait, what’s that distinctive chatter coming from under the bonnet, the lively rasp from the exhaust that has replaced the familiar pushrod drone? And just check out the rev counter: it’s the familiar white-on-black Jaeger job, but keep accelerating and the needle will pass 7000rpm before it hits the redline. It’s a British roadster, Jim, but not as we know it.

The ’50s and ’60s were a time of dramatic change for MG. With the A it abandoned the upright grille and embraced the new fashion of curvaceous, all-enveloping bodywork. With the Twin Cam came an exotic engine and the B brought monocoque construction to Abingdon. 

‘Designed to steal your heart’ the ads proclaimed when the MGA took a bow in 1955, and it’s every bit as pretty as the Jaguar XK120 whose curves it apes. If anything, its lower lines and more purposeful stance make it even sleeker than Lyons’ legend, with long front and rear decks and the short cockpit an afterthought between. The sides are almost austere in the way they avoid decoration, with not even a door handle to interrupt the lines. The nose and tail, in contrast, boast lots of chrome, fussy piping in the panel joints and generous badging. On a Twin Cam only the badges – plus the distinctive D-type-style centre-lock steel Dunlop disc wheels – give away the hottest A of all. Inside, it still takes an MG gnome to spot the difference: there’s that higher-reading tachometer and a matching speedo, plus the coupé’s Rexine-covered dash and slightly thicker De Luxe seats, but otherwise it’s standard-issue A. 

Yet this model was always more about what lay beneath: the competition-inspired power unit and the all-round Dunlop disc brakes that reined it in. Conceived by John Thornley as motivation for a halo model to take on Porsche’s all-conquering 356 in the USA, the twin-cam engine was designed initially by Gerald Palmer at Morris, based around the standard car’s B-series block. It was then refined by James Thompson and Eddie Maher after Palmer’s departure to Vauxhall, enlarged to 1588cc to make the most of its chances in 1600cc class racing and gaining siamesed bores in the process. After seeing off a rival proposal from Austin, the unit made its debut in an ex-Le Mans MGA in the 1955 Dundrod TT. It developed a misfire and retired – a depressing precursor to the engine’s production life – but BMC’s Competitions Department persevered and the twin-cam unit went on to power the 170mph EX 179 record-breaker and, in supercharged form, propelled EX 181 and Stirling Moss to over 245mph.

It was 1958 before management was confident enough to fit the engine into a road car – and not before time, the Twin Cam’s claimed 120mph top speed boosted a sports car range whose sole model had managed a maximum of just 98mph when tested by The Autocar. So does the addition of a couple of cams turn the traditional Brit into a Latin lovely? Not quite – in the same way that giving Joyce Grenfell a couple of implants wouldn’t transform her into Gina Lollobrigida – but it does add a sparkle to the MGA’s performance that better suits its chassis. 

The steering is heavy – accentuated by the smaller wheel on this car – so unlike its Italian contemporaries this isn’t a car you can steer with one hand leaving the other to wave ciao to the ladies. It’s a sports car that requires commitment, but put that effort in and the A rewards with a classic ’50s driving experience. With stiff suspension and sharp steering, it feels more alive than the MGB that replaced it. The heavier engine loads 53.1% of the Twin Cam’s 977kg over the front wheels so there’s a good dose of initial understeer, but it’s always happier when the tyres are squirming and the majority of the steering is being done via the throttle pedal.

Despite its higher power peak, the engine retains the B-series’ torquey nature and, unless you’re really pressing on, there’s no need to work the gearbox hard. This example boasts a five-speed Ford unit, but with a quick-shifter it does a passable impression of the original – positive, short-throw and satisfyingly mechanical in feel. Fourth even pulls the same 4000rpm at 60mph as the standard unit did in top – it’s easy to see why owner Davies opted for the conversion. This car, like many today, also runs lower-compression pistons to reduce stresses inside the tender motor. From launch, the 9.9:1 compression ratio was one of the scapegoats for the trouble-prone Twin Cam’s problems. It chowed oil – The Autocar’s testers found they had to add a quart every time they refuelled – there were cooling problems and piston failure was common. 

Customer complaints – and the ensuing poor reputation – led to the promising model being withdrawn after only 2111 had been made, just 2% of total MGA production. Ironically, it was taken off sale just as it was starting to become reliable enough to stand the inevitable comparison with more exotic models from the Continent. And they would provide stiff competition. Alfa Romeo was a proven specialist in twin-cam engine design long before Palmer put pen to draught-paper, and in 1954 it launched a new generation of sporting models with the lovely Giulietta – named after Shakespeare’s ill-fated heroine, Romeo’s perfect partner.

Launched as the Bertone-styled Sprint coupé, it was swiftly followed in 1955 by the berlina and Pinin Farina Spider versions, the latter a natural rival for the MGA in performance and accommodation – if not necessarily price. But while its sparky 65bhp motor just about gave the Giulietta the pace to live with an MGA 1500, it would have been decisively out-punched by the 108bhp Twin Cam. Fortunately, the boys from Milan made a pre-emptive strike just a year after the Spider’s launch with the hugely desirable Veloce. 

Retaining the near-square all-alloy unit’s 1290cc capacity, the Veloce replaced the standard car’s single downdraught Solex carb with a pair of sidedraught Weber 40s, which meant the engine had to be canted over in the small bay and required a redesigned sump. With a higher compression ratio and a tubular manifold, the result was 90bhp at 6500rpm  – quite enough for a sports car that weighed just 935kg. 

Like the Twin Cam, the Veloce didn’t shout about its extra performance – there was almost nothing to distinguish it from a standard car at a glance. But, again like the MG, the basic mixture was so right that to over-egg it would be criminal. Glitzy face aside, it’s a simple, relatively unadorned design from a carrozzeria at the height of its powers. The little Alfa shows clear overtones of the Lancia Aurelia B24 Spider that came before it, in particular in the proportions and the way the wing line kicked up over the rear wheels, with gently flared arches to complete the delicately detailed shape. 

It lacks the Oxfordshire Twin Cam’s overtly sporting intent – it’s certainly less sleek and rides significantly higher – but then the Giulietta is a particularly effective touring car. Compared to the tiny boot beneath the MG’s tapering tail the Alfa’s luggage bay is huge. There’s a spacious cabin too, beautifully assembled by Pinin Farina with proper wind-up windows, protective quarterlights and a relatively simple hood instead of the MG’s ridiculously fiddly canvas top and screw-on sidescreens. 

And it’s an effective touring car that will still keep up with a well-driven MG. Step from one to the other and it’s hard to believe they are contemporaries, such is the Alfa’s contrasting modernity. The light, surprisingly direct worm-and-sector steering makes the car feel agile, darty, a sensation that’s only accentuated by the lively twin-carb Veloce engine. Stir it with the slick but long-throw gearlever – a four-on-the-floor instead of the column change of the first cars – to get the needle spinning round the delightful Veglia rev counter and the little 1300 comes alive, with an extra burst of energy at 5000rpm, a zinging exhaust and an appetite for revs that even the MGA can’t match. 

Turn-in is sharp and there’s a good deal of roll, but the accompanying tyre protest and breakaway you anticipate never comes. The tyres grip with amazing tenacity, balance is superbly neutral and the ride soft, the stiff monocoque resisting scuttle shake at least as well as the separate-chassis MG. If there’s a complaint it’s that the floor-hinged pedals are awkward and the brakes – twin-shoe finned alloy drums all round on this early 101 Series car – can’t get near those of the Brit for power or directional stability. 

When American authority Road & Track got its hands on a Veloce in the late ’50s, it was blown away by the little Alfa Romeo, calling its engine ‘one of the smoothest fours ever built’ and extolling the virtues of its chassis: ‘One of the best handling sports cars you can find, at any price... well put together, beautifully finished, and a sheer pleasure to drive.’ 

With that kind of rapturous reception, it’s no surprise that a large proportion of the 17,096 Giulietta Spiders built joined the majority of MGA production on the other side of the pond.

Introduced in the same year, yet both aesthetically and dynamically a generation apart, the Giulietta and MGA appeal to very different audiences despite their on-paper similarities. A great example of each will set you back around £25k, which makes the Alfa Romeo – well over twice the price of the Twin Cam when new – a modern-day bargain. But if you’re in the market for one it’s unlikely that you’ll even consider the other. Despite its exotic configuration, the Twin Cam can’t disguise the MGA’s core appeal as a throwback to the 1950s: a chap’s car, at its best driven hard on a sunny day or drawing admiring glances on the gravel drive to one’s country retreat. The Giulietta was a look ahead at the ’60s, whose comfort and style made it ideal for continental touring yet whose eager engine and sublime balance gave it the arsenal to shame more focused machinery on the track. As its name suggests, it has all of the chemistry of Romeo and Juliet – but none of the tragedy.


MGA Twin Cam Roadster

Sold/number built 1958-‘60/2111 Construction steel box-section chassis, with steel body Engine front-mounted, iron-block, alloy heads, dual-overhead-cam 1588cc in-line ‘four’, with two 1in SU HD6 carburettors Max power 108bhp @ 6700rpm Max torque 104lb ft @ 4500rpm Transmission four-speed manual with synchromesh on 2nd, 3rd and top (Ford all-synchro five-speed fitted), driving rear wheels Suspension: front independent by wishbones, coil springs rear live axle, semi-elliptic leaf springs; lever-arm dampers f/r Steering rack and pinion Brakes discs Length 13ft (3962mm) Width 4ft 10in (1473mm) Height 4ft 2in (1270mm) Wheelbase 7ft 10in (2388mm) Weight 2156lb (977kg) 0-60mph 13.3 secs  Top speed 114mph Mpg 21.8 Price new £1027 (’59) 

Alfa Romeo Giulietta

Sold/number built 1956-‘62/2796 Construction all-steel monocoque Engine front-mounted, all-alloy, dual-overhead-cam 1290cc in-line ‘four’ with two twin-choke sidedraught Weber 40DCOEs Max power 90bhp @ 6500rpm Max torque 87lb ft @ 5300rpm Transmission all-synchromesh four-speed manual, driving rear wheels Suspension: front independent by wishbones, coil springs and anti-roll bar rear live axle, trailing arms, central A-arm, coil springs; telescopic dampers f/r Steering worm and roller Brakes drums Length 14ft 10 n (3900mm) Width 5ft 7n (1540mm) Height 4ft n (1310mm) Wheelbase 8ft (2250mm) Weight 2060lb (935kg) 0-60mph 14.1 secs  Top speed 112mph Mpg 26 Price new £2619 (’59) 

This article originally appeared in the October 2007 issue of Classic & Sports Car magazine, which retains the copyright to all words and images.

Words: Alastair Clements; pictures: Malcolm Griffiths