BUY-101 is a review of the numbers you might find on the MGA. Hang on, it's a long course. The following items are detailed below:.

Car Number Body Number Chassis Number Engine Number

Block Number Tachometer Drive Cylinder Head Number Carburetor Type

Gearbox Number Rear Axle Number Differential Gear Ratio

Carla Bender wrote:
    >>"I am looking at a 61 MGA--I am told it is a 1600. I have the VIN number and was wondering if there is a place I can check out any info by using the number?"<<

You could try checking with NAMGAR. I have no idea what success you might have there. Their original reason for existence is (or was) to register as many MGA as possible and to maintain a data base on the cars and the owners. I had been a member of NAMGAR for 15 years (until just recently), and in all that time the only thing I ever heard about the data was an occasional statistical report noting how many were produced in each color, how many were repainted, how many were currently red. One time they published some data relating engine numbers to car numbers, and thought this should be predictable within a range of about 200 numbers. I have never seen anything else about this data base published, and I have never known anyone to be able to get any answer at all (or even any response) to your question. They don't seem to be very responsive to members, let alone non-members. If anyone should have different results here, please let me know.

For a nominal fee and a moderate wait you can obtain a Certificate of Origin for the car from British Motor Industry Heritage Trust. This would list the specifics of the configuration of the car as it left the factory, including numbers for Car Number, Body Number, Engine Number, Gearbox Number, possibly the rear axle or differential number, gearbox type, final drive ratio, paint color, any special options, and the original delivery point. This is a nifty bit of history for a car buff, and it might be of some help if you have any problem convincing the DMV that your numbers and title are legitimate, or if for some reason you might be wanting the DMV to correct some erroneous information on the title, like reinstating the complete VIN number or changing the model year. It is not unusual for a current legitimate title to have only the last 5 or 6 digits of the Car Number. Even for the earlier cars, the DMV would sometimes drop the rest of the characters and retain only the serial numbers and this could happen any time the title changed ownership and was re-registered.

For the most part, very little of this has any bearing on the current condition or value of the car, unless you happen to be one of the very small minority of Concours enthusiasts. After more than 40 years of life in the real world, many of these cars have had engine transplants or cylinder head changes, some have had the body changed, and some even have a different frame by now. And all of this is not much to be concerned about, as the interested public generally considers these cars to be daily drivers, as originally intended, and not show cars.

    >>" .... is there anything specific I should be asking?"<<

Yes. Very specifically, does it have a clear title? And does the Car Number on the large tag on the heater shelf in the engine bay match the VIN number on the title? If so there should be no problems with the legality of ownership. Beyond that, almost any configuration of parts is generally acceptable, as long as it visually resembles the original configuration. If it looks like an MGA, it is an MGA. Non-MG engine transplants are generally frowned upon. A smaller displacement MG engine than the original issue can detract a little from the value. Odd paint colors are a matter taste, but can limit the resale market, so may detract from the value. The single most critical question about the car is not a number at all, but what is the condition of the body sills? Please read Opening Your First Rust Bucket. Don't be frightened by the page title, but do take the content seriously.

Car Number:

Vehicle ID plate bearing the Car Number

Next prominent point is that the body number is not the legal ID for the MGA, it's the "Car Number". The Car Number is (or should be) found on a large plate screwed to the heater shelf in the engine compartment. Click here for more information on the format of the Car Number and for originality of the Car Number Plate The Car Number, which is the common Vehicle Identification Number for the MGA, should match the VIN number on the title. In fact it pretty much has to match in order to register that car, or you might at some later date be accused of Grand Theft Auto. Some titles may use the engine number for the VIN, but that can get you in trouble if there is an engine change later. This alone should not keep you from buying the car. If the VIN on the title matches the engine number you can generally process a legal title transfer, but you should seriously consider having the title corrected to match the original Car Number. The important legal question is whether the title is legitimate, and you can even "correct" the physical numbers on the car if necessary, as long as you legally own it. The VIN number on the title should match at least the last 5 (or 6) digits on the large ID plate that is screwed to the heater shelf. After that you can get away with swapping out almost anything else on the car, and the state licensing agency could care less (except maybe California). The complete Car Number does not appear anywhere else on the car, but the last 5 or 6 digits are the chassis number, which may be stamped on the frame (see below).

There are a few concerns, primarily that the car you're buying should have a correct and legal title. To that end you should consider if the stated Car Number is at least in the right range for the stated model year on the title. In that era the cars were commonly titled in the year they were sold, so a car built in 1957 might have a 1958 title, but not the other way around. A friend here recently bought a legitimate 1963 MGA, even though the last MGA was manufactured in June 1962. This car was about 50 units from the end of production, and it just happened to sit on a dealer's lot for some months before it was sold and first titled. If the number on the VIN plate in the car matches the number on the title, and that number appears to be in the ballpark for the production period, and the title appears to be otherwise legitimate, you're cool. For a coarse estimate, the Moss Motors Ltd MGA parts catalog lists dates and serial numbers for the beginning and end of production of the four basic models of the MGA, the 1500, the Twin Cam, the 1600, and the 1600-MK-II. For more accurate dating and numbering you can consult "Original MGA" by Anders Ditlev Clausager (available from Moss Motors). This book has a list of serial numbers and production dates for all of the significant changes during the production life of the MGA.

Body Number:

Vehicle body number plate near the bonnet hinge

There are some other things to check if you were concerned about matching original numbers and parts. There is a body number on a stamped steel tag attached (should be spot welded) to the vertical firewall near the right side bonnet hinge. This does not match the Car Number on the large ID plate, and it is of little concern to anyone except a die hard concours fan, and there are precious few of those in the world. It is not uncommon for a car body to have found its way from one chassis to another during some prior repair or restoration work.

From Robin Barker on 27 October 2002
NAMGAR produces a "Worldwide MGA Database" which lists over 11,000 MGAs known to 12 different MGA groups around the world. The 2nd and latest edition of this database was published in June 2000 and documents the chassis #, engine # and body # reported to these groups by their owners. Records range from cars still with their factory original engine and body all the way to cars pieced together from 2 or more parts/donor cars. With so many cars in the database it is easy to pick out the original numbering sequences used by MG for both engines and bodies. The many cars with transplanted engines stand out as do the few with non-original bodies.
It appears that MG started numbering bodies at 20000 for the first MGA 10101 in 1955 and just kept going until reaching body # 79000 at about MGA 66600. Remember that there were a few Twin Cams in there as well which used body #s in the same range so the number of 1500s and Twin Cams built seems to about equal the number of 1500 style bodies built.
For some unknown reason, after MGA 66600 the body #s seem to have started at 1. The owner of MGA 66883 reports engine # 15GDUH5727 and body # 205. The owner of MGA 67176 reports engine # 15GDUH5871 and body # 473. There are many other reports of low body numbers like this. The highest is from MGA 68833 with engine # 15GDUH7540 and body # 1941.
With the introduction of the MGA 1600 at 68851, both the engine and body numbers change to 1600 type. The earliest report is of MGA 69047 with engine # 16GAU259 and body # B203.
The conclusion is that your body and engine are as installed at the factory. MG simply used low body numbers for the last 2000 or so MGA 1500s. Possibly the original plan was for the 1600 to reach production a little earlier. When this did not happen MG may have simply ordered 2000 more bodies and kept building the 1500.

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Chassis Number:

Chassis number stamped in frame below hand brake lever

There is or originally was (usually) a chassis number stamped into the top of the lateral frame rail (under the carpet) near the tunnel on the right side (basically below the ignition switch). Supposedly the chassis number should be the same as the Car Number on the ID tag screwed to the heater shelf. Check this offsite link to Chassis Identification (PDF document) for more detail of location and size of this stamping. This number is not stamped very deeply into the metal, and it is often obliterated by any attempt at cleaning off rust or glue during a process of repainting the frame in that area. It may even simply evaporate through the process of accumulating decades of light surface rust, so don't be concerned if you can't find it at all. And even if you should actually find a legible number there, it is also not uncommon for a frame to find it's way into a different car during restoration or repair. This is happening more commonly as time passes. I know a few people who are currently in the process of installing a replacement frame (used/repaired salvaged from a different MGA) during a restoration.

Engine Number:
For the MGA 1500 cars, at least through 1958, the original engine number was stamped on the large ID plate along with the Car Number, and the Car Number included a few other things, like the paint color code for the body. For later cars the box on the ID plate for the engine number was simply printed with "See Engine", and most of the extra characters in the Car Number may have been left out leaving only a 5-digit serial number for the Car Number (or maybe 6 digits with a leading "1" for the latest production from early 1961 through June 1962).

Engine number plate at top edge of engine block

The engine number, if it still remains, would be found in raised stamped numerals on a small aluminum tag attached to the top corner of the engine block with two drive rivets just below the head gasket between #2 and #3 spark plugs. It is not uncommon for the tag to be missing (and no great crime either). During the machining process for re-boring the cylinders for an engine rebuild the engine block is normally "hot tanked" for cleaning, and this process will dissolve the aluminum tag if it was left on the block. If there is a tag there it is not unusual for it to be somewhat mutilated from the process of removal and reinstallation, or it might be a spanking new issue created to replace a missing or damaged tag. It is also very common for the engine to be a replacement unit, in which case it should have a different number than the original engine. In the end, only a real concours enthusiast would even care if the engine number was as original. It might be of some concern that the engine should be the original type, as having a 1500 engine in a 1500 car, but even that is of little concern for a daily driver. My 1500 car currently carries a 1600 engine with a cylinder head from an 1800 engine, and I have a 1622 engine under the workbench for a spare. It is usually considered fair game to mix and match these engine parts, except that people don't usually like an engine that is smaller displacement than original, and a fair number might actually object to an MGB 1800 engine in the MGA, even though more would welcome it with open arms.

For the MGA Twin Cam engines, the engine number plate was attached to a horizontal surface on the rear of the engine behind the cylinder block.

Engine Block Number:

Engine block size number above left engine mount

You can look on the left side of the engine block just above the engine mount bracket. Here you can find a large raised number cast in the block, 1500, 1600, 1622, or 1800, which is indication of the original life of that part.

Tachometer Drive:

Mechanical tachometer drive cable attachment to engine

At the left rear corner of the block, sort of hiding below the carburetor heat shield, there should be the attachment point for the tachometer drive cable (looks just like a speedometer drive cable). All MGA and early MGB with the 3 main bearing engine had this mechanical tachometer drive. Later MGB, starting in 1964, had the 5 main bearing engine and no mechanical tach drive. If the car carries a 5 main 1800 engine it will have to have been switched to electric tachometer. There are also some 1500 and 1600 and 1622 engines originally used for other applications (such as the 1500 MG ZB Magnette) that may not have the mechanical tach drive.

Cylinder Head Number:

Cylinder head number

Look on the top of the cylinder head at the back, just aft of the valve cover flange. Here you may find a large raised number in the casting. "15" was used for the 1500 and 1600 engines. This one could be a bit of a fooler though, because it was also used for the 1500 engine in small valve single carburetor cars like the Nash Metropolitan, and with that you might get much smaller intake valves and the performance of a 40 hp VW Beetle. Bummer, but it's hard to tell without removing the cylinder head for inspection. There are certain casting numbers on top of the head inside of the valve cover, but lots of variations there, and no telling if a rework has changed the valves to a larger size in a past life. "16" was used only for the 1622 engine of the MGA 1600-MK-II.

"18" was used for the MGB 1800 engines through 1971. Starting in 1968 all MGB heads (at least in the USA) had air injection ports near the spark plugs. "L" was used for MGB heads 1972-1974, and those had larger intake valves and higher compression (but single valve springs rather than dual). Then back to '18" for later heads. Some replacement heads had no number here, and you have no idea what valves those might carry. The 1975 and later heads had a water take-off port on top at the rear corner to supply the hot water controlled choke on the single Z-S carburetor of the rubber bumper MGB.

Carburetor Type:

Original type SU H4 carburetors

You might find various carburetors on an MGA. For that discussion read "Alternate Carburetors". Otherwise all MGA (except the Twin Cam) originally had the same twin SU H4 carburetors (with a couple different numbers for various fuel jets). You might also find that the original cast iron exhaust manifold has been replaced by tubular headers, which is no great crime, but it can be a little noisier, and it may not improve performance noticeably unless it is done in conjunction with some upgrading of the cylinder head and carburetors..

Gearbox Number:

Gearbox number on top near dip stick

There were five different gearboxes used in the MGA over the years of production, three different propshafts, two different starter positions in the bellhousing, two different clutch disks. The gearbox number can be found stamped on top of the gearbox next to the oil level dip stick. This is not very easy to get at, as the oil fill hole and dipstick is accessed through a hole in the top right side of the tunnel under the dash. Good luck in finding a good line of site to read this number without disassembling something major. If you can get there, it will look like the picture above. These are simple serial numbers, not containing any extra characters to designate the specific model of gearbox, so unless you have a comprehensive cross reference list you will have to judge by the appearance of the parts. Find that discussion in the Gearbox Tech section. All original units were manual 4 speed with three synchronized gears, non-synchro 1st and reverse gears. There was a moderately rare close ratio gearbox most often found in the Twin Cam or 1600-MK-II Deluxe cars. The gearboxes have been swapped out at least as often as engines, so don't count on having the original unit. .

Rear Axle Number:

Rear axle number

The rear axle number is stamped on the front side of the left hand axle tube. I found mine just inboard from the rebound strap, about over the exhaust pipe, and just above the weld line in the axle tube. This one says "11586 10/43". The first numbers are the axle serial number. The last numbers are the (original) gear ratio. The rear axle is generally quite robust and durable in the MGA, but a common reason for changing it is to reconfigure from disk wheels to wire wheels or vise versa. The wire wheel axle housing and half shafts are about 7/8" shorter at each side to allow for the length of the splined hub. Wire wheels may be preferred for appearance. Bolt on wheels may be preferred for the availability of more options for competition or appearance. .

Differential Gear Ratio

Final drive ratio stamped on differential housing

The final drive ratio is stamped on the front of the differential housing near the top bolts.
10/43 = 4.300:1 for 1500 and 1600 cars
10/41 = 4.100:1 for 1600-MK-II
 9/41 = 4.556:1 commonly used with close ratio gearbox for competition.
11/43 = 3.909:1 optional and rare when new, but now more common as a modification.
Other ratios were available on special order.

So there you have it. The only number that really matters is the Car Number stamped on the large ID plate on the heater shelf, and the matching number on the title.

As a matter of reality, it is not unusual for someone to mix, match or swap out almost anything or even everything on the car in the process of restoration. If you happen to have in your possession most of one good MGA with no title, and one legal title (key word is "legal") with no useful car to go with it (presumably parted out or scrapped) you can do some creative restoration work. You could obtain a new ID plate to replace a missing or damaged one, and you can stamp on it the legitimate and legal ID number matching the (presumably legitimate) VIN number on the good title. Thereafter you may attach this plate to the car body of your choice, and place that on the frame of your choice, and attach that to pretty much any combination of parts to reconstruct and restore your car to something resembling the original configuration. Then you go apply for the license plates to put your freshly restored MGA on the street, and you have one very nice and totally legal car. And because it was a legal title to begin with it probably doesn't even have to be inspected, depending on your state of residence (watch out for California).

There are just two restrictions that apply here to keep it legal. You must legally own all of the component parts (nothing reported stolen and some reasonable belief of ownership), and you are limited to registering only one car for each legitimate title and Car Number. In other words, the legal ownership goes with the title, and if the car resembles the original issue, everyone's satisfied. There are even a few avenues for legitimizing some possibly questionable title, or for sort of "re-creating" the legal title for a car that might currently have as little as a bill of sale, but I wouldn't elaborate too much unless you have such a need. The point is that it's pretty tough for an MGA with a clear title not to be a certifiably legitimate MG. Just keep repeating to yourself, "It has to be a clear title". Otherwise if you like the car, buy it.