MGA TWIN CAM AT 60
60 years after the MGA Twin Cam was first shown to the press, C&SC joined the enthusiasts re-enacting the launch
Enthusiasts gather to celebrate by recreating the sparkling model’s launch
Anniversaries are seldom marked with such precision, but 60 years ago to the day, this very place witnessed the launch of the new MGA Twin Cam. Today happens to be 14 July, and we’re at the Longcross Proving Ground – formerly the Fighting Vehicles Research & Development Establishment – at Chobham in Surrey, for a Re-enactment Event organised by the MGA Twin Cam Group of the MG Car Club.
“It was my idea to recreate this 10 years ago,” says Mark Hester. “When I became TC Group chairman, this event was one of my first goals. Edward Vandyk touted it as a mini Goodwood, complete with tweed jackets and everything! Once I knew we were aiming for that standard we had to up our game, and I think we’ve done incredibly well; we’ve got nearly 60 cars here – the largest-ever gathering of Twin Cams.”
The Twin Cam story began when MG officially entered the 1955 Ulster TT with three MGAS. Two had experimental twin-cam engines: one was a clean-sheet design by Austin (which was a no-show); the other was based on the B-series block developed by Jimmy Thompson and Eddie Maher at Morris Engines (initially under BMC’S chief designer, Gerald Palmer). It was the Morris design that would be pursued, via the EX179 record car, in the name of offering superior performance to the 68bhp 1489cc pushrod car. The plan was to make the MGA a better rival for Continental sports cars and more appealing for competition use.
MG’S first production twin-cam engine had originally been envisaged as a 1489cc unit, but changes to competition classifications led to a capacity increase to 1588cc. Its chain-driven twin camshafts were housed in an aluminiumalloy crossflow head. Running on twin SU H6 carburettors and with a 9.9:1 compression ratio, the Twin Cam had forged H-section conrods and a stiffened three-bearing crankshaft in a B-series block bored out to 75.4mm, underpinned by a finned alloy sump. The new engine was 60lb heavier than the 1489cc B-series.
The MGA Twin Cam featured Dunlop knock-on wheels, ‘Twin Cam’ badging, a leather-trimmed fascia and four-wheel disc brakes. Priced at £1265 17s (including Purchase Tax), the new 108bhp MG was capable of 115mph (against the standard A’s 99mph), and trimmed 1.7 secs off the 1500’s 0-60mph time (the Twin Cam completed the sprint in 13.3 secs). It was faster from 0-90mph by 15 secs, too (the Twin Cam took 30 secs). Yet the price premium for all that extra pace was just £180.
Ultimately, just 2111 of the planned 2500 Twin Cams were built, as the model developed a notoriety for a lack of smooth running, plus noise and reliability issues. It was easy for a piston to hit a valve due to the engine’s eagerness to rev. (Vandervell tested its new Tri-metal crank bearings in this engine because it was one of few capable of running above 7500rpm.) At the very least, 95RON fuel and N5 spark-plugs were recommended for road use, 100RON with N58RS for competition. A piston-ring issue initially led to fouled spark-plugs, but perhaps the most infamous problem was that it gained a reputation for melting pistons, which led to a lowering of the compression ratio to 8.3:1, but was eventually traced to the 1¾in SUS running lean due to engine vibration at certain revs. The model was axed in 1960. Leftover Twin Cam parts would find a home in the De Luxe and De Luxe MKII, powered by the 1622cc B-series.
The 1958 launch we’re celebrating here was organised by Nuffield Publicity and described as a ‘Nuffield Competition Day’. In addition to six Twin Cams and the record car EX181, Rileys and Magnettes were present, too. However, not one Austin-healey attended, underlining the partisan disarray at BMC.
Just four Twin Cams were available to drive (PMO 326, 325 and 946), with one car (VLP 500) being borrowed from University Motors. In addition, two prototypes were used for demonstration: the first example (ORX 855) and static display (PJB 147). Why? Morris Engines’ Courthouse Green factory didn’t have a large enough machine to balance the crankshaft, flywheel and clutch as a single assembly, so they balanced them separately with mixed results – half of the engines suffered from vibration at high rpm when run in. To ensure that it only had
“The pushrod MGA is a gentle, easy-going sort of car; the Twin Cam has excellent performance, but it’s quite demanding”
good specimens for the launch, MG had run a selection of cars for 24 hours at Grove airfield.
In charge of the day’s proceedings was 29-year-old Geoffrey Iley, for general manager John Thornley was in New York on business. Ironically, when Iley started at MG, Thornley had said: “Your job is to get the cars out the door. I’ll deal with design, development, the press and everything else.” Despite this, in 1958, he was here, overseeing 42 staff, hospitality, entertainment, the cars and the guests.
Today, as Iley approaches his 90th birthday, he remembers: “On the day, we had the beer tent because that was for the press. If you remember in those days, motoring journalism ran on alcohol, methanol and fags – and to hell with health and safety. All went tolerably well during the morning. The motoring press was there in droves, with the likes of John Bolster and Gregor Grant of Autosport, Bill Boddy of Motor Sport, people from The Motor, The Autocar and from around the world. There we all were, liquid flowed in the beer tent, the Morris Motors band was there and when they went out, most of the time it was fairly well disciplined.
“During the afternoon, somebody – I’m not sure who – suggested a fastest lap of the day competition. After that, it was all hubcaps and doorhandles… The fastest lap was set by Paul Frère, with John Bolster second fastest of the day, and I blush to admit that I was third fastest. A long way down the field and the slowest of the day was Bill Boddy of Motor Sport. All went well after that. We finally managed to get rid of everybody, and when we were sweeping up the
broken bottles and clearing up the site, we counted the cars and found we had one fewer than we started with. Panic!
“A trip around the circuit revealed one of the Twin Cams wrapped around a concrete bollard with two people not looking very well. It was driven by a junior mechanic and his passenger was a cornet player from the band who sustained a broken pelvis. As a result, we had a major row with the musicians’ union, which was one of the more entertaining industrial relations problems with which we had to deal!”
At last, Hester gives me the keys to PJB 147, one of the prototypes that was here in 1958, with a few words of advice: “The valves bounce at 7200rpm!” The engine is vocal, you can hear the rasp of the chain-driven cams. It isn’t as sweet as some twin-cam contemporaries, but this linear yet perky lump doesn’t half shift when prompted. Indeed, given that this engine was a starting point, its unfulfilled potential is lamentable.
The low-slung driving position – backside placed between its chunky perimeter chassis and propshaft – sets the sporting mood. The controls feel precise and alive. The slim gate of the mechanically slick, remote-change four-speeder, the twin-cam’s enthusiasm, the steering’s deftness, gearing, feel and responses are all underpinned by the chassis’ immense solidity, its amicable handling and composed ride.
Today it’s too hot to tease this 60-year-old’s redline and, given its importance, I’d like to return it before there’s a danger of stepping into the scenery – one incident from 1958 which should definitely not be re-enacted.
Thanks to the MG Car Club’s MGA Twin Cam Group (www.mgcc.co.uk/mga-twin-cam-group), and to Mark Hester and Edward Vandyk
Clockwise from top: the organisers’ work paid off with five original launch cars; Baron’s Us-sourced MGA; grainy photo from the Nuffield Organisation shows the 1958 event in full swing; map of the test track given to participants
Binnington cares for this special, one-off, Le Mansclass-winning Twin Cam. Above: 1588cc dohc ‘four’ has 108bhp and 104lb ft of torque as standard
From top: snug, beautifully finished cabin – steering wheel is a stylish period accessory; Twin Cam owners keenly take to the Chobham test track; Mark Daniell and son George with their two racers