The overdrive four-speed automatic is replacement for older three-speed Turbo Hydra-Matics or two-speed Powerglides
Many classic cars that used an original Powerglide two-speed or TH-350 three-speed can benefit from installing a TH-200-4R four-speed automatic without having to perform major modifications. The 200-4R can be used on many other GM passenger cars because it was manufactured with both a Chevrolet and a B-O-P bellhousing bolt pattern. The taller, fourth gear allows the engine it is installed behind to rotate at lower RPM than a three-speed transmission, and this not only will save on gas and engine wear, but it also allows you to change to larger rear axle ratios without severely impacting streetability.
TH-200-4R transmissions are very easy to locate from salvage yards, and most replacement parts are still available from transmission parts suppliers and auto parts stores. Heavy-duty parts for racing applications are available from transmission parts suppliers, as well.
Will a TH-200-4R fit in my car?
Your engine size should be a consideration; many muscle-car enthusiasts recommend using the TH-700-R4 or 4L80E overdrive units on large V-8 and higher performance engines. However, in many V-6 and small V-8 applications, a TH-200-4R will fit with fewer modifications.
The TH-200-4R, like the TH-350, uses a 27-spline output shaft, which is similar in length to the TH-350 and the TH-200, making it a natural for many overdrive conversions. The TH-200-4R is also similar in length to the Powerglide and the B-O-P Super-Turbine 300 (two-speed), which makes it a popular unit for converting from a two-speed to a four-speed automatic.
The TH-200-4R has a 2.74:1 first gear ratio, and overdrive is 0.67:1. Its odd-shaped 16-bolt pan has 13mm bolt heads. The TH-200-4R was used in GM rear-wheel-drive cars equipped with the 231 Buick, 301 Pontiac, and the Oldsmobile 307, 350 gas and 350 diesel engines from 1981-’90; however, many Chevrolet 267 and 305 V-8s also used the TH-200-4R because of the multi-fit bellhousing.
The transmission identification is on a plate on the right side of the case towards the tailshaft. This ID plate is attached by one rivet. The plate will have a two- or three-letter transmission code in large letters.
Which TH-200-4R should I get?
The most desirable TH-200-4Rs for performance enthusiasts are the units manufactured for Buick Grand National, Olds 4-4-2 and Chevy Monte Carlo SS in 1986-’87. These units used a special valve body. They also had a larger reverse boost valve, second to third intermediate servo, and a specially designed governor assembly. Their BQ, OZ, CZF, KZF or BRF transmission codes can identify these more desirable units.
This transmission is ideal for swapping with a TH-350 or a Powerglide, because the overall length and the bell housing bolt pattern of the TH-200-4R are the same, and your original driveshaft does not have to be shortened. The output shaft is 27-spline, the same as the TH-350’s. Moving the crossmember will be necessary, because the TH-200-4R crossmember is mounted on the extreme end of the tailshaft.
Great examples are common, and restoring one couldn’t be simpler
The easiest collector cars in the world to own are those you can get the most parts for. You can probably name a lot of them: the ’55-’57 Chevy, the early Mustang, the first-generation Camaro, the Triumph TR6, the MGB, and so on. As grows the hobby, so does that list (as do the criteria for being on it—which now includes complete reproduction steel bodies), but since the beginning, included the 1928-’31 Ford Model A.
The complete history of the Model A as a sensational new car – including its proven durability during the worst of conditions of the Great Depression and World War II, and its popularity as a simple and easily improved used car in the shortage-wracked postwar period – is too detailed to get into here, but suffice it to say that the historical popularity of the A translates to an extremely robust and complete aftermarket still supporting these cars on the eve of their centennial. Even in as-delivered form, the Ford Model A remains an eminently driveable car—married with some improvements developed when it was nearly new, it can traverse virtually any 21st century road with ease.
There are plenty of opportunities to do so, too. Two clubs serve the Model A hobby specifically: The Ford Model A Restorers Club (MARC) and the Model A Ford Club of America (MAFCA). They maintain technical libraries, advisors, and most importantly, communities of enthusiasts with whom to trade ideas, tribal knowledge, parts, and information. Both organizations are variously tolerant of modifications pioneered in the A’s earliest days as a used car, especially when the appearance is kept stock or made to resemble a period speedster or race car.
Many of those changes blend seamlessly into a road-ready car, ideal for participating in tours like those organized by MARC, MAFCA, and the local chapters thereof, plus multi-marque events run by other organizations. Moreover, unless you live in a really congested area, a touring-grade Model A makes a great fair-weather driver for any purpose —assuming your insurance provider and licensing authority agree.
Speedsters and more heavily modified cars will find themselves welcome at other sorts of events, including hill climbs and traditional hot rod gatherings like The Race of Gentlemen. Beware, though: Beyond a certain point, the more heavily modified the engine, the more temperamental it becomes and the shorter its lifespan.
The standard Ford closed body for all years of production was the two-door sedan (spelled Tudor by Ford, to complement its naming the four-door sedans Fordor). It also proved the most popular in original production, with 523,922 built in calendar-year 1929 alone (Ford didn’t track body-style production by model year) and 1,281,112 by the end of ’31 production in early 1932. Most in-demand today are the roadster and coupe bodies. The former is reproduced, and though repair panels are obtainable, no complete closed Model A body is. A late-1928 to 1931 Tudor makes perhaps the ideal Model A owner’s car for a variety of reasons, not least of which is the prospect of extra leg room in the front seats, attractive price point in the current market, and an all-steel body (compared with the wood-framed Fordors, built by outside suppliers). It’s on that specific model that we’ll focus here.
Engine and drivetrain
While it’s a flathead four-cylinder, and parts from the Model A engine have been made to work in the Model T block, there’s not much in common between the 177-cu.in. Model T engine and the 1928-’31 Model A engine, which displaced 200 cu.in. and made 40 hp at 2,200 rpm —twice the T’s 20 hp at 1,600 rpm. Famously, one reason the Model A is often seen wearing a quail radiator mascot is because its abrupt acceleration reminded operators of that bird bursting forth from the underbrush. The four-cylinder retained its reputation for quick starts right up through the V-8 era, when owners of “bangers” preferred to race from a standing or low-speed rolling start (the origin of the drag race) against V-8 owners. The V-8’s longer-legged nature was reflected in the popularity of the greyhound mascot on ’32-’34 Fords.
In its stock form with a heavy flywheel, the Model A engine remains a roadable unit, though it’s hard for most owners of driven cars to resist internal improvements when rebuild time comes along. Upgrades to the oiling system are popular, as are counterweighted Model B crankshafts (which permit a lightened flywheel and installation of a later clutch). Replacement of the poured bearings with modern-type inserts are frequently discussed, but probably overkill on anything but an engine regularly driven hard.
Top-end modifications, including additional carburetors (both stock-style updraft and later-style downdraft), high-compression (this is relative —stock used a 4.22:1 ratio) cylinder heads, high-performance camshafts, and free-flowing exhaust manifolds all exist and are of varying utility depending on the owner’s intended use of a Model A. Some more compression (Ford itself offered a Police head, though aftermarket heads usually boasted a superior chamber design and more compression yet—anything in excess of 6.5:1 is not advised with poured bearings), a distributor incorporating centrifugal advance (stock units are driver-adjusted from the steering wheel—not a situation favored by every modern driver), a Model B-grind camshaft, a downdraft two-barrel carburetor (Stromberg types being a good compromise between period tech, flexibility, and present-day parts availability), and a cast-iron exhaust manifold will give a healthy enough boost to any engine that you may wish to look into some of the brake upgrades discussed below.
Some A owners have gone even further than modifying the factory engine, yet without straying all the way into V-8 territory. More than one Model A has received, complete, the 50-hp four-cylinder engine originally found in a 1932-’34 Ford Model B. Aside from an external fuel pump, the Model B block looks very much like the Model A, yet it hosts oiling improvements and a counterbalanced crankshaft. Opinions diverge on whether the earliest 1932s had the balanced crank, but the real split in desirability seems to stem from Ford’s switch from sweated-on to cast-in counterweights, the latter of which aid immensely in rebuilding.
The Model B engine was originally packaged with a heavily revised transmission. The original Model A unit was scaled down from the big Lincoln transmission in use in the late 1920s — complete with multi-plate clutch. That clutch was soon replaced with a conventional disc unit, but the heavy flywheel and unsynchronized gears remained. When synchromesh was introduced to the marketplace, however, the consumer wouldn’t long stand for the necessity of double-clutching, and lighter flywheels had the added benefit of letting an engine gain rpm faster—though to the detriment of shifting unsynchronized transmissions.
For 1932, the Model B transmission was essentially that of the V-8 car, but in a gear case designed to work with the four-cylinder. In fact, gearsets from Ford passenger cars up through 1948 will fit in the Model B case, though it’s tight. Because the Model A bellhousing also mounts its pedals, many B-powered A’s will have been modified to accommodate the Model A oil pan, bellhousing, and transmission. Alternately, a variety of schemes have been worked up to use Model A pedals with later transmissions, including swaps intended for the Borg-Warner T-5 five-speed, the Ford SROD four-speed, and the 1932-’39 Ford V-8 three-speed.
Transmission choice complicates the rest of the driveline, as Ford cars built through 1948 had their driveshaft enclosed in a suspension member called the torque tube. The Model A axle, though theoretically not as strong as the V-8 units of 1933-’48, will mate with the later Ford transmission without modification to either. Adapters to fit the SROD and certain models of T-5 to the torque tube have been offered, and some enthusiasts choose to switch to an open driveline. That latter option is complicated, however, because the radius rods alone were not designed to deal with the braking and acceleration forces of the rear axle.
The Model A came with a standard gearing of 3.78:1 while V-8-era Ford axles were typically 4.11:1, so swaps to later rear axles are possible but rarely performed unless seeking added strength during a V-8 swap.
I purchased an early Model B gearbox a while back at a good price, (3 years ago!! but never took things any further but now back on the radar) not in the best condition but appears to be serviceable. The other parts I’ve been gathering with the help of John Cochran. (need any Model A bits, he’s your man)
There are a fair number of parts needed to complete the conversion, but I think it’s worthwhile as its a synchronised transmission. The later unit is supposed to be a better option but we’ll work with what we have and it’s a good project to take into 2023.
As you can see some of the parts need some work. There are a number of differences between the Model A and Model B set up. Major items are the clutch housing, flywheel, relocation of the pedals and wishbones just to mention a few.
Made a start on the shift tower which had some rust and debris that has fallen into the gearbox, this however should be easy to remove. The unit was filled will gear oil when I originally purchased it to keep things lubricated during storage. As you can see even with a cursory initial clean up on the shift tower, things look a lot better.
During the clean up I came across the part number which is cast into the casing, stating 40-7222, which was a little confusing as this is the earlier transmission.
A quick check over at the excellent VanPelt site quickly solved the mystery
The 40-7222 shifter housing (known as the “slanted” tower) pictured below was used from 1933 through 1935 models. The B-7222 housing (1932 only) looked the same but had two mounting bosses on the right hand side for the parking brake handle mount. Both early housings incorporated the B-7235 shift lever guide plate (see picture at bottom of this page). The guide plate was discontinued after 1934 production. The early housings used the B-7230 and B-7231 forks through 1933 and perhaps part of 1934 production. The slanted towers used the smaller 7230/7231 shifter forks, but also used the smaller shifter levers. Although it will bolt on to any 1932-52 toploader gearbox case, it can NOT be used with the 1939 and later gear sets with the late style synchronizers. This housing is the single detent type, using the same detent spring and plungers as the 68-7222 housing.
It’s the car that put a wrench in many a young enthusiast’s hands
Like a lot of things, auto restoration has antecedents in the pre-World War II era, but is most strongly associated with the postwar period. Brass car enthusiasts were already preserving and fixing those machines by the late ‘30s, but the first thing that most would recognize as the hobby/industry of today really springs out of the post-war DIY movement centered on the 1928-1931 Ford Model A.
Why the Model A? Well, a bunch of reasons…
Background on the A as a new car
Like the early Mustang, the Model A was a sensation when it first came out in late 1927, and Ford was hard pressed to keep up with the demand. From an engineering standpoint, it was strictly evolutionary, not revolutionary: The chassis, based on transverse leaf springs and solid axles front and rear, was very much like that of the 1909-’27 Ford Model T but with the addition of shock absorbers and front brakes.
Stylistically, the new Ford was patterned after the Lincoln Model L, though today both cars are often confused with the Model T because the subtleties of styling evolution in the late-‘20s/early-‘30s have been lost to the non-enthusiast public over the decades. Regardless, what was perceived as a handsome car in 1929 has endured as a period icon to later generations. It’s also more welcoming to most drivers compared with a Model T, both for the improved chassis and the seemingly more familiar three-speed, floor-shift gearbox—virtually the industry standard by then, though Ford had clung to a 1900s-tech two-speed planetary transmission through the end of Model T production.
To rectify the various perceived shortcomings of the Model T, a huge aftermarket industry had grown up around Ford in the 1910s and ‘20s. It turned its attention to the Model A immediately, though those attentions were severely interrupted by the October 1929 stock market crash (right about the time 1930 Fords arrived in the showroom) and the ensuing Great Depression. The resulting products were memorable, as they were intended to improve upon an already excellent, 40 hp car rather than bring a 20 hp 1909 car up to the present standard, and have been intermittently produced up to the present day
Influence of the A as a used car
Basic, stock Fords proved their durability in the Great Depression, and well-used examples are frequently seen in period photographic efforts by the Farm Security Administration, a New Deal Agency that employed many talented photographers to document the plight of rural immigrant families fleeing the Dust Bowl. While the Joad family may have driven a Hudson Super Six in The Grapes of Wrath, far more itinerant working families traveled the U.S.A. in Model A’s held together by optimism and ingenuity.
A Ford Model A roadster pickup like this 1928 Ford Model A roadster pickup (“Open Cab Pickup”) in the Hemmings Classifieds would make a great shop truck or long-distance hauler with just a few period upgrades.
This one caught my attention because it’s nearly identical to the one we have in the Sibley which was once dragged to TROG. I saw it there for the first time, and I’ve harbored ambitions about turning that little pickup into something with a bit of 1940s flavor ever since. Talking to Jeff Koch about his plans for his family’s 1931 coupe re-energized my appreciation for Ford’s 1928-’31 masterpiece and the myriad ways people have found to improve them since. Jeff wants to walk the line between hot rodding and touring using some newer equipment, but left to my own devices, I’d always hew closer to how Ford developed its cars from 1928 to 1948. It’s a good lesson for making any ’20s car a better driver without sacrificing the vintage experience.
Although the Hemmings pickup is the one I see most often, any ’28 or ’29 would fit the bill. It’s mere coincidence that this one is also a Commercial Green (Rock Moss Green? Something like that) 1928 model. The Hemmings truck is somewhat rarer as it is an early 1928 with the slightly nicer looking splash aprons and the hand brake near the door, Model T-style. Supposedly, Pennsylvania didn’t permit the early design, hexing a big potential market for Ford. I seem to recall the objection was that the hand brake was used to set the rear-wheel service brakes, but PA required separate systems for emergency/parking brakes and service brakes.
No matter, all those interesting old parts, new design or old, could be removed and preserved someplace after a proper pickling/mothballing. In their place would go the best of early 1940s technology, starting with 12 x 2-inch hydraulic drum brakes, front and rear. Up front, I’d go with new Lincoln-style units from Bass Kustom and in back, Ford-type brakes, as they’re somewhat easier to retrofit to an early axle. The Lincoln units have the advantage that Ford chose to license Bendix’s self-energizing technology for its up-market brand, whereas regular Ford and Mercury cars stuck with the Chrysler-Lockheed type through 1948.
The original axles and Houdaille shocks, if in good condition (and the listing says the little pickup has only “88 miles since completion” of a “complete frame-off restoration,” so they ought to be) can stay. If not, there’s always longtime Hemmings advertiser Apple Hydraulics. If my planned tires (which I address below) look a little lost under the fenders, a reverse-eye front spring is a good way to get the nose down slightly without resorting to dropping the front axle
You could probably run this fairly mild engine against the original un-synchronized three-speed, but it would really up the ease of driving if you followed Ford’s route and adapted a V-8 gearbox with synchronizers on second and third gears. The 1932-‘34 Ford Model B used a trans behind its 50hp four-cylinder that was internally the same as the V-8 models but used a different case. Now, you can put any 1932-’48 Ford passenger-car transmission or 1932-’52 light-truck three-speed behind a Model A engine using an adaptor from Cling’s. The pinnacle of early Ford V-8 transmission technology is widely agreed to be the nice-shifting ’39-’52 Ford floor-shift three-speed (exclusive to trucks from 1940-on) containing ’46-’48 Ford passenger-car or close-ratio Lincoln-Zephyr gears in order to mate with the enclosed driveline.
The Ford Model A ammeter (amp meter) is at the center of the Model A electrical system. Today, Model A Ford mechanic Paul Shinn shows you how to modify the typical reproduction ammeter to make it safer, and as a bonus, how to make it look more like an original. If you don’t want your Model A to break down, just subscribe! http://www.youtube.com/user/paulshinn…
There are two general types of Speedometer for the Model A – the oval and the round bezel is the most obvious difference from the outside. On the inside, they are entirely different, too – so since this thing landed on my bench, I decided to do a teardown and repair video on this one, too. Enjoy!
People are always asking “What’s the number on my Model A engine mean?” Is it a serial number? Is there a record of what body style and color of car the engine was originally installed in? Can it tell me the date my Model A was built? This video tries to briefly explain the history of the Model A engine numbers and what information you can find out about your car from it.
Using 22 different archived videos spliced together this video depicts the Model A engine being produced, from sand molds to being dropped in a chassis. Every Model A engine destined for one of Ford’s 30+ US assembly plants was cast and assembled at the Rouge Plant in Dearborn, MI. Make sure to look out for the main bearing babbitts being poured, the flywheel being balanced, and the manifolds being assembled. How did we do? A Model A is dedicated to the history of the Model A Ford using historical images and videos as well as modern resources.
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