Smith's classic british cars
Classic british sports cars. MG, Triumph, Jaguar, Morgan, Austin Healey, AC, Morgan, Lotus - the legends, the performance, the heartbreaks.
For Classic British sports car fans, the 1955 to 1962 MGA is one of the best choices for an affordable, easy to maintain classic car. Whether buying a basket case, finding a well-used original, or considering the purchase of a restored MGA, shoppers can rest assured that they'll have a ready answer to a question that plagues many a classic sports car owner: "Where can I find parts?" The answer is as easy as flipping through a catalog. Try that with an Alfa Romeo Spider Veloce.
MGAs were offered in three basic configurations from the car's launch in 1955 to its final incarnation in 1962. From 1955 to 1959, MGAs were powered by 1,498cc pushrod engines. Beginning in May of 1959, MG introduced the MGA 1600 Mark 1, with not only the benefit of a more powerful engine, but disc brakes up front. From March 1961 until May 1962, MG sold the final edition of the MGA, the 1600 Mark II. From 1958 to 1960, MG also offered the MGA Twin Cam.
After the end of Twin Cam production, a handful of 1600s were built on the Twin Cam chassis, with its four-wheel disc brakes and center-lock steel wheels; these were unofficially regarded as "deluxe" models, but MG never referred to them that way. Since they used the four-wheel disc brakes, they had separate brake and clutch master cylinders, which meant that the heater box had to move to the opposite side from standard pushrod cars. In effect, pushrod cars equipped with the Competition Suspension package featured a hybrid body and frame with a special configuration around the heater shelf. There were actually three different versions of this car, depending upon its build date.
There are several ways to identify the different models, beginning with the relevant numbers affixed to the car. The car number, found on a plate screwed to the heater shelf under the hood, should correspond with the VIN shown on the title. Until some time in 1958, this large tag is also where you would locate the engine number. Post-1958 non-Twin Cam cars have the engine number on an aluminum tag between the #2 and #3 spark plugs. Over 40 years and multiple engine rebuilds, you can safely assume that this tag is either a) lost, b) destroyed, c) incorrect, or d) a reproduction. On Twin Cams, look for the engine number on a similar plate at the back of the engine block near the transmission bell housing. There is also a gearbox number stamped near the gearbox oil fill hole, but good luck reading it. On the front of the left-hand axle tube is the rear axle number, along with the original axle ratio, which is also stamped on the front of the differential housing. The Body Number, which does not correspond to the car number, is spot-welded to the firewall, close to the right-hand hood hinge. There is also a chassis number, stamped into the frame just below the handbrake. This number can be hard, even impossible, to read, but it should correspond to the car number.
Here's something else to keep In mind, especially If you're buying a Twin Cam: "The twin cam engine gained a bad reputation for reliability," Twin Cams did not sell particularly well at the time, needing an engine rebuild every few thousand miles. With the modern parts available today, this has become a very reliable and desirable option and a good example can cost 20'000 USD more than an equivilent pushrod motor.
There are several exterior identifiers for the MGA, beginning with the trim and badges for the air vents mounted on top of the front fenders. All MGAs, regardless of engine size or year, have "MGA" cast into the middle rib of the air vent. 1500s will have no accompanying badge near the air vent. The 1600 has a "1600" badge accompanying the air vent. 1600 Mark IIs have a "1600 Mk II" badge, and 1600 Twin Cams have a "Twin Cam" badge. Similarly, an identifying badge is placed under the octagonal MG logo on the rear trunk lid, identical to those found near the air vents.
Aside from badging, the biggest tipoff to the presence of a 1600 Mark II is the grille. Every other MGA features the same grille, a twin-nostril piece with 14 chrome vertical bars in each side. 1600 Mark IIs are similar, but the bars are pushed back at the bottom edge, and feature an extra surround between the grille casing and the bars.
Other identifying differences can be found in the car's front and rear lamps. The marker and turn signal lamps on 1500 and early Twin Cam models are small, and feature clear lenses. Later Twin Cams and 1600s have larger lamps, with the marker and turn signal lamps separated. North American cars would have completely clear lenses, while the rest of the world had amber turn signals. At the rear, 1500s and early Twin Cams have all-red Lucas rear taillamps mounted on the rear fenders. Later Twin Cams and 1600s feature larger, fender-mounted taillamp escutcheons with separate lamps for amber (or clear in North American cars) turn signal lamps. 1600 Mark IIs saw new, ovoid combined taillamps moved to the rear valance, just below the trunk lid.
The biggest differences between the MGA roadsters, of course, are the engines. The MGA 1500's engine was based on the 1,200cc Austin A40 engine, which was introduced in 1947. Heavily revised for 1953, the engine saw a 300cc increase in displacement. The first MG to use the engine was the MG Magnette ZA, which was introduced at the 1953 Motor Show. The engine then went on to power the Morris Oxford Series II and the Austin A50 Cambridge, meaning that there's no shortage of spare engines around. The first MGA engine carried the engine number BP15GB. In 1957, the engine number was revised to 15GB-U-H. The "U" signified the revision to a center gearchange, and "H" indicated higher compression. In 1959, the engine was revised again, this time to the 15GD-U-H.
All the 1500-series engines have the numerals "1500" cast on the side of the block opposite the spark plug inlets. GB-type engines can be identified by a blanking plate over a hole for a mechanical fuel pump used in Austins and Morrises, but never on the MGA. GD-type engines do not have this blanking plate. 1500s with correct GD engines also have a slightly different transmission tunnel, right-side toeboard and carpet, thanks to a change in the mounting of the starter.
Between April of 1958 and May of 1960, MG introduced the 1600 Twin Cam, which shared 1,588cc displacement with the MGA's 1600 pushrod engine. Like the 1600, the Twin Cam's block was cast iron, but instead of an iron cylinder head, the Twin Cam's was cast of aluminum alloy. Identifying a Twin Cam engine is as simple as looking for the twin aluminum rocker covers. Correct Twin Cam engine blocks will also have a plate riveted to the back of the block with the designation "16GB-U."
May of 1959 brought the 1600 engine, with a displacement increase from 1,489cc to 1,588cc. Early GC-type engines are identified by the numerals "1600" cast into the block. The 1600 Mark II signified the final engine change, and can be similarly identified by the numerals "1622" cast into the block.
A handful of options were offered on the MGA from introduction. Perhaps the most important option may have been the aluminum hardtop offered on early MGAs. Thanks to their aerodynamic nature, they allowed the MGA a 3 MPH higher top speed, and were used in racing. Due to their expense, they were not popular, and are therefore very valuable today. A later fiberglass hardtop was available, which is still desirable, but be sure it's not an aftermarket unit if it's being billed as an original MG option.
Thanks to the British Motor Industry Heritage Trust, you can find out exactly the options with which your MGA (or any MG built between 1953 and 1980) was ordered. For about $60, and $5 postage, the BMI Heritage Trust will send you a Heritage Certificate indicating the history of your particular car, traced by chassis number.
In my opinion, the MGA is one of the easiest cars to restore from the standpoint of the availability of aftermarket reproduction parts at reasonable prices. (New chrome bumpers made in China are about $100.) In fact, I would bet that it's easier to restore an MGA today than it would have been 30 years ago.
In general, all the MGA engines offered are robust and easy to work on. Blocks for all the engines (including the Twin Cam) are readily available and cheap. 1500s are cheap to the point of being free. With the exception of the size of the pistons and cylinders, the 1500 and 1600 engines are identical, and all the parts are interchangeable. Unless you're wildly concerned about originality, faced with a 1500 with an engine block beyond repair, a good, rebuildable 1600 block is probably the way to go. It's even somewhat accepted in the MG community to upgrade to an MGB's 1,800cc engine if you're planning on driving the car any significant mileage. When rebuilding, consider a new cam over a used one, as MGA cams can suffer significant wear.