Buyer's Guide: 1928-1931 Ford Model A

Model A SpecificationsEngine 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.

Body and chassis

The Model A frame changed very little in over four years of production. Early on (over the first half of 1928), the braking system changed to separate the service brakes from the parking/ emergency brake, which left evidence not only in frame changes but in modifications to the splash aprons and the wheels. When a taller radiator on the 1930 models appeared, that required some changes as well, but in 96 years, necessity has resulted in the invention of ways to make things work together. In other words, don’t despair if you find evidence your 1929 was rebuilt sometime with a 1931 frame —as long as it was done right, it should be fine.

If a frame is out of whack, the simple, ladder design is easily straightened and repaired. Aftermarket frames, frame rails, and crossmembers exist, but they are aimed almost exclusively at the street rod part of the hobby— one exception being reproductions of the oft-mangled front frame horns. Stock or lightly period-modified cars usually stick with Ford pieces. Frame-up restorations aren’t as common for Model A’s as they once were, but should you find yourself with a car apart for some reason and are contemplating the aforementioned conversion to a V-8 transmission, drop-in crossmembers replicating modified 1932 Ford parts exist to accommodate both transmission and pedal mounts.

Modifications to the Model A braking system are hotly debated. The original four-wheel mechanical-drum system was a vast improvement over the Model T’s transmission brake acting only on the rear wheels, but even Ford saw fit to improve the system a few times before converting to hydraulic brakes for the 1939 model year—perhaps most notably in a switch from stamped-steel to cast-iron drums in the course of Model A production. From a performance standpoint, hydraulic drum brakes of the 1939-’48 Ford Lockheed design (or the 1936-’49 Chevrolet Houk design, for that matter) offer no improvement over properly adjusted mechanical drums of equivalent size and acting on an equivalent contact patch.

Mechanical brakes are, however, far fiddlier to adjust than hydraulic systems and the modern hobbyist often doesn’t take much joy in that task. Luckily, neither did the 1940s DIYer, so the engineering of putting ’40-’48 Ford brakes on a 1928-’31 Ford was worked out long ago. Better yet, because those brakes are widespread in the traditional hot-rodding scene and the V-8 restoration scene, all the parts from backing plates and drums to wheel cylinders and shoes are available brand new.

On the flip side, if you’re evaluating a car that someone put “juice” brakes on years ago and it has been sitting, watch out. Mechanical brakes don’t go bad from lack of use, but hydraulics do!

If you’re looking for extra braking ability, aftermarket kits for fitting reproduction 1940s Lincoln self-energizing hydraulic brakes are available, as are modern linings and “floaters” for improving the friction and shoe contact in the stock mechanical system.

The braking system on a Model A has consequences where wheels and tires are concerned. The very early 1928 cars had brake drums and wheels unique to themselves. Thereafter, and through 1935, Ford mechanical brake drums had supports for the wire wheels incorporated into the face. Ford hydraulic brake drums from 1940-’48 had the same 5 on 5.5-inch bolt pattern, but lacked wheel supports. Add-on supports are advisable when running 1928-’35 wires on later hydraulic drums. Likewise, later Ford steel wheels don’t seat properly on the early drums.

Because of the commonality in bolt patterns, images in the ’30s and ’40s frequently show otherwise-stock A’s running around on 18-, 17-, and especially 16-inch wire-spoke wheels from later Fords. Even when the Model A was brand new, aftermarket wheels were a common accessory and popular for their ability to provide oversized tires with a greater cushioning effect.

Suspension

Often derided as “buggy sprung,” the transverse-leaf Ford suspension was simply a different approach from most of the industry, which preferred parallel leaves by that point. Because the basic system was used by Ford from 1909 to 1948, it became very refined. Because 1909-’48 parts underpinned most of American motorsport through the late 1950s, a lot of thinkers after Ford’s engineering staff have also worked on improving it.

As a road car, the well-maintained, in-spec Model A is fine unchanged. Roads today are generally much better than those of the early 1930s, so even a stock A can run up near its potential top speeds a lot of the time. The inclusion of a wheelbase of over 3.5 inches more than the Model T, plus hydraulic shock absorbers on all four wheels, meant that the A feels a lot more stable at higher speeds than its immediate predecessor. Still, there are sympathetic improvements to be made here based on later practice.

The Houdaille lever-action shock absorbers, if in good shape, should give fine service. Often, however, previous owners of even ostensibly “stock” driver-quality cars have discarded worn-out lever shocks for tube shocks. Ford itself made that change part way through 1947, and it’s a functional system that actually dates back to the 1930s on some non-Ford cars like Nash and Chrysler products, so “airplane shocks” are period tech that improve, rather than compromise handling if otherwise properly matched to the chassis.

Going further, without entirely departing from period practice, the Model A steering gear’s somewhat crude design was improved upon by 1937. Ford didn’t produce an easily interchangeable steering box until 1948 —though certain Nash and Hudson boxes from the ’30s were workable swaps as well. Today, aftermarket suppliers offer F-100 pickup-style steering that bolts right into an unmodified Model A and even contains provisions for the headlamp, horn, spark, and throttle controls. Like the synchronized three-speed from a V-8 Ford, the swap to a later steering box is said to turn a nice-driving little car into a great-driving one without sacrificing the essential experience of operating a vintage machine.

Interior

The standard, five-passenger interior for all four years of production was covered in cloth rather than leatherette like the open cars. Shades varied from year to year, and carpets were replaced with rubber flooring sometime late in 1928. The oval-speedometer instrument panel of 1928-’29 was replaced for 1930-’31 by one with a round speedo. Accessory gauges —and panels to mount them like the dramatic Aristocrat panel made by Dunn Manufacturing Company in Clarinda, Iowa, which added spots for two additional instruments —have been popular additions since new and a set of refinished vintage pieces add utility to the simple Model A cockpit. Since the demise of famed supplier LeBaron Bonney, the Cartouche brand (owned by Mac’s and thus by Eckler’s) has seemingly become the go-to supplier for Model A interiors, though smaller operations like Classtique Upholstery in Lindstrom, Minnesota, haven’t gone anywhere either.

In conclusion

The Model A walked the line perfectly as a new car: inexpensive but not austere; simple but not grimly utilitarian. Those virtues make it a great car to own today. It’s capable, easily worked on, easily obtained, and above all—fun.

The Tudor sedan is perhaps the most essential of all Model A’s. Their initial popularity means they’re easy to find today and their comparatively sensible nature when compared to the glamorous roadsters, phaetons, and coupes mean that they’re not suffering from an overheated market due to competition from hot rodders.

If you’ve ever contemplated owning a pre-World War II car, it’s hard to recommend anything more highly than a Ford Model A Tudor.