MGA: The Archetypal Sports Car

For many people, when someone says vintage sports car, the MGA is the iconic image that comes to mind. The flowing, curved body design with oval hood is one of the great automotive designs of all time, and it was a radical departure from the staid, upright MG TC, TD, and TF.

Plus designers paid great attention to details and performance. To streamline design, there were no exterior latches. To reduce weight, the doors, hood, and trunk lid were skinned in aluminum. The XPAG engine found in the TC, TD, and TF was replaced with the more modern B-series engine from the MG Magnette. The MGA was among the first high-volume production cars to offer four-wheel-disc brakes and a twin-cam engine as options.

Is it any wonder that the MGA captured the imagination of car enthusiasts when it debuted in 1955? The car went on to sell more than 100,000 units, the first British sports car to do so.

Production Delay A Benefit
The MGA was originally designed to debut years earlier. The first prototype for what became the MGA (known as UMG 400 and EX172) was a re-bodied MG TD designed by MG’s Syd Enever for George Phillips to race in the 1951 24 Hours of Le Mans. Only a scale model was wind tunnel tested, but Phillips hit 116 mph on the straights at Le Mans thanks to the aerodynamics.

A road-going version of the car was proposed to British Motor Corporation management in 1952 as the TD replacement. The full prototype (EX175, registered as HMO 6) had the old TD running gear and 1250cc XPAG engine combined with a wider chassis and MGA body shell. Faced with limited corporate resources, Leonard Lord gave priority and funding to the Austin-Healey 100 instead.

The two-year production delay enabled MG to refine the design, and launch the car with the newer 1489cc inline four-cylinder B-series engine and transmission. The delay also meant that the car could be thoroughly race tested. The company entered three aluminum-bodied prototypes (EX182) into the 1955 Le Mans, and they finished respectably. So when the model debuted soon after the race, its competition record helped establish the pedigree of the breed.

MGA Models
When it launched, specs for the MGA 1500 in stock trim were good for its day: 68 bhp; 77 lb.-ft. of torque; top speed 91 mph; and 0-60 mph in 15 seconds. The separate body and frame, lever shocks, solid axle, rack-and-pinion steering, and low center of gravity made it handle well. The car weighed 1,988 pounds and featured drum brakes, bolt-on steel disc wheels, wood floorboards, synchromesh on the top three gears, a soft top, and side screens.

Over the eight-year run, there were four models—the 1500, Twin Cam, 1600, and 1600 Mark II—and there were Deluxe versions of the 1600 and 1600 Mk. II. All the models were produced as roadsters and coupes, although less than 10 percent were coupes. There were few exterior changes between models.

MGA Twin Cam

To give the model a huge leap in power and an advantage on the race track, MG introduced the Twin Cam in 1958. The B-series engine displacement grew to 1588cc, and an aluminum cylinder head incorporating dual overhead camshafts was added. The model also received Dunlop disc brakes all around and center-lock disc wheels. It had 108 hp and 105 lb.-ft. of torque with top speed of 114 mph.

But the bugs hadn’t been worked out in the rush to production, and the car was labeled as quirky and unreliable. Although the remedy was determined fairly quickly, the early reputation did the model in, and only about 2,100 were made during the two-year run.

In 1959, the 1600 launched with a pushrod version of the 1588cc engine producing 80 hp and 97 mph top speed. Disc brakes were on the front wheels only.

The 1600 Mark II debuted in 1961 with a larger displacement engine (1622cc), an improved cylinder head, bigger valves, revised grille, and some interior refinements. It produced 93 hp and delivered a 102 mph top speed. Deluxe versions of these two models used leftover Twin Cam frames, brakes and wheels; 395 were produced.

MGA production ended in 1962 as the MGB took over the MG flagship honors.

Drivability Determines Value
Kelvin Dodd, Moss technical expert and MGA owner, admits that the Twin Cam is the holy grail since it’s the most developed of the MGAs, but points out that they are rare and expensive. He believes it possible to build a better performing car so long as you’re willing to veer away from originality.

“It seems MGA values are still based on drivability,” explains Dodd. So a MGA 1500 in stock trim isn’t worth as much as a MGA 1500 with an 1800cc MGB engine, so long as it appears original looking.

“You could take an original MGA 1500 that is reasonably priced since it has the smallest engine and drum brakes, and bolt in a number of upgraded components without permanent modifications, and you’d be able to knock a Twin Cam into the weeds performance-wise,” says Dodd. “I get calls about this all the time.”

The Ultimate MGA
Dodd’s ultimate MGA incorporates an 1800cc engine from an MGB, a five-speed gearbox, a supercharger, an aluminum head, performance exhaust header, stainless steel exhaust, MGB front suspension kingpins, new MGB adjustable front sway bar, and Wilwood disc brake kit.

Engine swaps are popular since the 1800cc engine is available and is a direct bolt-in, explains Dodd. “The five-speed gearbox makes the car a lot more drivable…it gives you synchro on first gear, an 18-percent gear reduction on the rear end, and more comfort while driving at highway speeds. A stock MGA can handle 70 mph, but it’s winding out, noisy, and thrashy at that speed. It’s screaming for a five-speed gearbox conversion.”

The supercharger provides up to a 40-percent power improvement for the bigger MGB engine, as well as the three original MGA engines. Dodd adds, “Remember that Judson made superchargers for the MGA back in the day, so it’s a period accessory.”

The aluminum head is lighter and cools better, says Dodd. If you don’t install a supercharger, a cross-flow head enhances your car’s tuning potential with four intake ports instead of the stock head’s dual ports. The performance exhaust header offers efficiency and improved exhaust flow-through, and is especially important with a supercharger, he explains. Combine that with a polished stainless steel exhaust system that replicates the original and uses the original hangers. “It’s a stunning work of art,” he says, adding that it’s the newest of the Moss-exclusive MGA products.

A front anti-sway bar makes a big difference, says Dodd. Moss sells an exact duplicate of the factory-supplied part, which mounts above the front fender support. He notes that installation requires a later-model front bumper support, and is best to install when in the midst of a restoration. As an alternative, you can install the new MGB adjustable front sway bar under the frame rail, but it requires some modifications.

With MGB front suspension kingpins, you can use the Wilwood Brake Kit that includes Wilwood aluminum four-piston calipers, drilled and slotted rotors, and braided stainless steel brake lines. “This brake setup is more sensitive, has better stopping power, and is less prone to overheating with a better caliper and larger piston area,” says Dodd.

MGA Enhancements
Even in stock trim, the MGA has a lot going for it since the car was well developed, says Dodd. So the original-spec dual SU carburetors, camshaft, valves, valve springs, rack-and-pinion steering, shocks, and suspension are perfectly acceptable.

But for owners looking to enhance their cars to make them safer, more reliable, and better running on an affordable budget, there are plenty of options. You could replace your cast iron cylinder head with a lighter aluminum head that won’t crack. A gear reduction starter is a real benefit, especially with the larger engine conversion, Dodd adds. You can replace the twin six-volt batteries with a single 12-volt. Replacing headlights with halogen lamps improves night driving.

In the electrical system, changing from a generator to an alternator provides a better charging rate and charging at idle, which is a good thing in traffic. But you’ll have to change the car over to negative ground, which is safer for jump-starting and a necessity for extras like a radio, explains Dodd. A conversion to an electronic ignition like a Pertronix with modern Cobalt plug wires is also popular. If you want it to look original, you can drop a Pertronix module into your original distributor and run original-type spark plug wires.

Cooling is an issue since the engine compartment doesn’t vent well. Employ a fan shroud, and be sure the seal between the radiator and bonnet are intact, advises Dodd. An oil cooler conversion kit helps too. Moss is working on a multi-blade plastic fan that should be available in the spring. For heat radiating into the passenger compartment, put Dynamat insulation around the transmission tunnel, he suggests.

Braking Options
Dodd says the drum brakes in good condition work fine if adjusted correctly. But owners installing a bigger engine or supercharger may want better stopping power, he says. Plus disc brakes are easier to work on and reject heat better. The 1500 had drum brakes, while the 1600 had disc brakes on the front, and the Twin Cam and Deluxe models had Dunlop disc brakes on all four corners.

Your options for converting a 1500’s front drum brakes to disc brakes depend on the type of wheels on the car. With wire wheels, all parts are available new. You’ll need MGA 1600 wire wheel hubs, MGA caliper brackets, calipers and MGA rotors. You have two options on calipers: original MGA calipers are now available new (recently introduced!), or you can get an alloy conversion bracket for MGB calipers, giving you a wider range of brake pad options.

You’ll have a bigger challenge if your car has disc wheels since the hubs are no longer available. If you can’t find used MGA disc wheel hubs, consider a MGB brake conversion using rebuilt kingpin assemblies. Dodd says there are many benefits to this approach: a stronger kingpin (MGA kingpins are prone to cracking), better wheel bearing design and less expensive rotors. The MGB calipers also open up more brake pad options.

But the downside is a more complicated installation. You’ve got to shorten the steering rack tie rods, and adapt the MGB upper kingpin to the shock. You can do this by installing MGB shock arms, or installing hardened spacers between the shock arm and upper trunnion, he explains.

Speaking of wheels, Dodd says that if your MGA has original steel wheels, be sure to get them crack tested. Wire wheel conversion kits are available. If your car has the original 48-spoke wire wheels, he recommends an upgrade to 60-spoke wheels.

Moss-Exclusive Products
There are plenty of MGA products that are Moss exclusives in addition to the stainless steel exhaust system and supercharger. There are exact reproductions of the turn signal switches; the MGA grille manufactured with a brass base covered with chrome plating like the original; an aluminum side curtain set based on the hard top side curtains; and fog lights and brackets made to the original specifications.

Interior and aesthetic elements are also available with precut, structural-grade plywood floorboard kits, a bolt-in burl wood dashboard to replace the steel dash, burl wood steering wheels, and custom-made seat covers just like originals with leather facings. There are plenty of options on tops, tonneaus and car covers, too. Grille badges with a badge bar can also be used to personalize a car. “MGA is a Moss favorite. We carry a full line of accessories for period-original and modified cars, and we continue to develop new products to meet the needs of MGA owners,” says Dodd.

For quick model identification, look at three key elements: rear lights, wheels, and badging. The 1500 and early Twin Cam had a single red vertical rear lamp; the late Twin Cam (engine shown above) and 1600 had two rear lamps with a round indicator light mounted above the tail/brake light; and the 1600 Mk. II had a single horizontal rear lamp. If the car has center-lock wheels, it’s a Twin Cam or Deluxe. The 1600, 1600 Mk. II, and Twin Cam have the model name next to the front/top engine air vents and under the MG logo on the trunk lid.

Insider’s Info:
The numbering for the MGA production run began at chassis 10101, a straight continuation from the last TF off the line, chassis 10100. The first six cars were used for testing and development.

The MGA double-wishbone, coil-spring front suspension with rack-and-pinion steering was designed by Alec Issigonis, father of the Mini, in 1938, and was carried over from the MG TF. It was such a strong design it continued to be used to the last MGB in 1980.

Without door handles on MGA roadsters, owners have to reach inside and pull a cable. There are no door locks, either.

The coupe versions had a high curved roofline and larger windshield than the roadsters, plus wind-up windows, outside door handles, door locks, and a trimmed dash.

MGA proved itself well on the racetrack with good finishes at the Mille Miglia, Sebring 12-hour race, Le Mans 24-hour race, Monte Carlo Rally, Alpine Rally, and Goodwood Whit Monday.

The 1956 MG EX179 was basically a MGA with a streamlined shell designed to challenge land speed records on the Bonneville Salt Flats. Top speed was 170 mph; at one time it held nearly 100 international and world records. Stirling Moss set class records in the revised EX181; it featured a supercharged MGA Twin Cam engine and hit 245 mph at Bonneville in 1957. Phil Hill hit 254 mph with a tweaked version of EX181 in 1959, making it the fastest MG in history.

The original selling price of the 1956 MGA 1500 Roadster was $2,195 in the U.S. The 1962 MGA 1600 Mk. II Roadster sold for $2,499.

Current prices range from about $5000 for cars needing restoration work, to $40,000-plus for perfect cars—both single- and twin-cam versions.

The MGA has been featured in loads of movies and television programs, from the James Bond movie, Diamonds Are Forever, to The Mod Squad, The Avengers, Mission: Impossible, Top Gear, and even the Beverly Hillbillies!

The North American MGA Register is the model’s largest national organization. It offers members a bimonthly magazine, annual Get Together, members-only technical information on the website, and a network of 2,300 enthusiasts. There are 52 regional chapters with meetings and events too. (

By Kathy Mangan
Photos by Walter Pietrowicz

'MGA: The Archetypal Sports Car' have 5 comments

  1. June 8, 2012 @ 6:18 pm Doug Widnall

    I have to disagree with you about putting an 1800 CC engine into the MGA. Upgrade the origional motor, add supercharging, whatever, but changing engine size is somehow wrong. Why stop there? Do the whole Frankenstein thing and add four more cylinders! Why the MGA? Why not drop a cobra 427 into a 1962 Jag? Get rid of all those carbs, Add some 19 inch rear mags and get rid of those flimsy wire wheels!
    My 1600,(MK1) runs just fine and keeps up with traffic and all the MGBs in the area, also handles as good as any “new ” car on the road. I’m not going to drag race any Miatas, but then again they don’t have my cars’ good looks. I think the more original the car is the better. these things are already 50+ years old now. do we have to start pushing non-original motors and decreasing the uniqueness of the original car to satisfy the hot-rod mentality of the gear-heads?


  2. November 23, 2012 @ 12:10 pm Jeff Z.

    It WOULD be nice to have the strength of a 5 main bearing engine instead of the 3 main bearing engine. For those moments when you are getting overly enthusiastic. You can always keep the OE engine in a crate in the garage, and nothing has to be cut or hammered for a neat fit.


    • February 20, 2013 @ 2:22 pm tim t

      regarding ‘engine strength’..the 1500 and 1600 BMC engine has an inherant weakness in its crankshaft. (the webs are thin and tend to crack with age and heavy use) there is dispute regarding 3 main 1800 and 5 main 1800 .. early factory race cars used the 3 main 1800 engine as a preference due to lower frictional losses. here’s some pro’s of the ‘3 main’ as an MGA upgrade:-the cylinder block is a direct ‘bolt in . the rod bearings have a larger surface area than those of the 5 main (hence,,last longer) the tach drive remains . its almost 30 lbs lighter than the 5 main unit. 5 main in MGA:- requires backlplate modification to take the rear oil seal . needs an electronic tach . wears its rod bearings before other engine components..and(as stated above) heavier short..there is NOTHING wrong with the 3 main can be improved with upgraded connecting rods (factory comp type are same as MGA twin cam..with larger fully floating wrist pins) ..several manufacturers supply improved rods which are substantially lighter and stronger and allow a much wider choice of piston due to fully floating wrist pin. .


  3. December 29, 2012 @ 1:50 pm Mike

    Good information. I think I am like many enthusiasts in that I intend to modify my MGA Coupe mechanically but keep it looking as original as possible, (i.e.” “restomod”). The joy of older cars is in driving them and seeing them on the road. For me, adding performance accessories makes the cars more enjoyable and more capable in modern road conditions.

    The 1800cc engine with a Moss blower, MGB suspension, and disc brake mods are great options. They keep the car close to being “all MG”. This is the direction the factory version may have progressed had the car continued to evolve. That said, I personally am not opposed to using a GM 3.4 liter V6, T5 transmission, and Hoyle IRS system either! Although more of an American-style “street rodder’s” approach, I think the car’s reliability and performance would be much improved and the car’s beautiful shape need not be altered.The advantage is that you are welcome at both custom car shows and British field meets!

    Once you change anything from original specificiation it is no longer “accurate” or “period correct”. If you are a purist and want to compete in concours events you need to use original parts. I appreciate the fact that many folks keep their cars standard. The MGA is a valuable part of automotive history and deserves to be preserved.

    Bottom line is, sports cars are for having fun, whether they are all original or customized.


    • May 28, 2021 @ 1:21 am Phil Cozens

      I like all comments for and against , but I have a one owner1958 red mga 1500 , I have resprayed the car ,seats and carpet re upholstered .
      Now after long consideration I am going to replace the motor gearbox with the 1800 MGB running gear front disc brakes oil cooler twin fans etc ect
      Including supercharged etc.
      Why do this you may ask ,I can say every time and I mean every time I drive my A down to the shops or the country I get the thumbs up ,
      So I am changing the running gear etc so I will enjoy my A even more , it will go as good as it looks .
      Keeping all original motor gearbox and parts in my warehouse on pallets in bubble wrap, for the future for my grandchildren or the next owners.
      All my conversion will be carried out by ( MG workshop Melbourne Australia ) a trusted workshop for all MG cars .
      It will always look original to the average person but drive like new 😀


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