In late 1959, Ford introduced a new lightweight unit-body compact called Falcon. As Paul has previously chronicled, the Ford Falcon “platform” survived in the U.S. through 1980, and spawned some of Ford’s biggest domestic-market hits, including the original Mustang. This success has led to a popular misconception that these various Ford models were essentially just different lengths of the same unit-body sausage, but it wasn’t that simple. Let’s take a closer look at the Falcon, Comet, Fairlane, and the ways their body structures were — and weren’t — the same.
Early Ford Falcon
The point of unit-body construction is to save weight and free up some interior space by eliminating the heavy, bulky separate frame. Although the body of a unitized vehicle has to be beefed up to handle its additional load-bearing responsibilities, there’s usually a net weight savings, as well as improvements in structural rigidity.
If you’re reading this article, there’s a good chance you knew that already, but even some enthusiasts are surprised and puzzled to notice that the underbody of a unitized vehicle often has visible rails and crossmembers, which look much like the pieces of a separate frame, and perform some of the same functions.
As this Ford “underbody plan” diagram shows, the darker areas on the above illustration of the 1960 Ford Falcon indicate “pseudo-frame” members: two sets of longitudinal rails joined by four crossmembers, plus the side rails (sills), which formed the rocker panels as well as the sides of the cabin floor. Instead of a rear crossmember, the trailing ends of each rear rail were connected by the body’s back support panel, which was made especially deep so that it could do both jobs.
These members were all welded to the Falcon body shell, whose dashboard, roof pillars, and roof rails also contributed to its structural rigidity.
So did the transmission and driveshaft tunnel, which formed a central “backbone” for the floorpan.
If you look back at the underbody plan, you’ll notice that the rear rails were connected to the side members by “torque boxes.” Isolated torque boxes are an extremely important concept in unit body structural design (and perimeter frames), and they seem to be very poorly understood. This kind of torque box is a metal structure that connects two longitudinal rails; it’s welded or bonded to both, but isn’t an integral part of either. The torque box acts as a kind of shock absorber: When force is applied to one rail, the torque box twists a little, soaking up some of that force without transmitting it to the other rail. The 1962 brochure for the later Ford Fairlane (which I’ll discuss more below) described the function of the torque boxes like this:
these boxlike structures are strategically placed to intercept road noise, vibration and ride harshness transferred from road to wheels to car. By torsion (twisting) action … very slight, but enough … the torque boxes effectively absorb these annoyances before they can reach the passenger compartment.
The 1960 Falcon was not Ford’s first use of this concept: The 1958 Thunderbird used torque boxes where the narrower front rails connected to the side members. Their original rationale was to absorb enough vibration and harshness that Ford could get way with using bolt-on front fenders rather than welding them in place for strength. Bolt-on fenders were easier to fix after a collision, and they allowed greater flexibility for styling changes. The early Falcon also used bolt-on front fenders, for the same reasons.
Front suspension on the Falcon (and on the later Comet, Fairlane, Mustang, and Maverick) was double wishbone, but the coil spring was mounted on a pivoting spring seat atop the upper wishbone, acting against a suspension tower welded to the steel “apron” that formed the side of the engine bay. This was only new for Ford: Rambler had used a similar front suspension since 1950, because the high-mounted spring reduced unsprung weight and allowed a longer, softer coil spring for better ride quality. (The later Chevy II did the same thing.)
Ford used diagonal braces to connect each suspension tower to the cowl structure. These braces provided a lot of the front-end torsional rigidity (resistance to twisting forces) in these cars, although their design varied somewhat from model to model and year to year.
The top of each engine bay apron was folded over to form an upper ridge, and was welded at the front to a rectangular bracket, welded in turn to the front crossmember. In later years, enthusiasts would bemoan the restrictive engine bays of cars built on this platform, but the ability to accommodate larger engines hadn’t been a design priority for the original Falcon, and this structure gave the early Falcon additional front-end strength while reducing total weight. Also, as Chevrolet found out when they used a similar front suspension for the early Chevy II, the suspension towers had to be very sturdy to withstand braking forces, especially with the high degree of anti-dive geometry in the front suspension.
Each lower “wishbone” of the front suspension was formed by a stamped control arm and a diagonal radius rod that Ford called a “drag strut.” The leading end of each drag strut had a soft rubber bushing and acted against a bracket under the front crossmember.
Falcon rear suspension was Hotchkiss drive, meaning semi-elliptical leaf springs that did double duty as control arms to locate the live rear axle. On an early Falcon (or Comet), there were five leaf springs, separated by butyl rubber liners to reduce the friction you get when leaf springs rub together. The leading end of the spring was connected to the rear side rail by a 2-inch rubber bushing, and the trailing end had a 3.5-inch-long compression shackle with its own rubber bushings, which were supposed to cushion the spring motion if the rear suspension bottomed out.
The rear shock absorbers were splayed inward, “sea-leg” style, with the upper shock mounts attached to the bottom of the rear crossmember. Angling the shocks inward this much did reduce their effectiveness somewhat, but it helped to provide lateral location for the axle, so it was fairly common when these cars were designed. Rambler and Studebaker did the same thing.
Behind the rear axle, the gas tank (which was bolted in place) was used to strengthen the rear floor, and the top of the tank actually formed a section of the trunk floor.
Ford boasted that the early Falcon had greater torsional and bending stiffness than a 1960 full-size Ford, even though the Falcon “body in white” (body shell with no trim) weighed 547 lb less. The early Falcon wasn’t really a very small car: At 181.2 inches overall on a 109.5-inch wheelbase, it was similar in size to an early ’90s Honda Accord sedan. However, it was impressively light, with a shipping weight of only 2,259 lb for a basic Falcon “Tudor” sedan. (The “Fordor” sedan was 29 lb heavier.) There were no special materials or new technologies involved — Ford simplified everything it could and then ruthlessly optimized every single component for weight and cost.
The light weight of the early Falcon paid off in economy, but it also became a liability in ways the designers hadn’t anticipated: As I’m sure CC’s Australian and Kiwi readers will attest, the early models were too lightly built for the pounding they took from driving regularly on rough or unpaved roads. The Falcon also hadn’t been designed with any provision for hardtops, convertibles, or V-8 power, which would have to be added later.
Early Comet
The first Comet was introduced early in the 1960 calendar year. Comet was a deluxe version of the Falcon, and was originally intended as an Edsel.
(Comet wasn’t officially identified as a Mercury until the 1962 model year, but people usually call the early car a “Mercury Comet” anyway.)
Comet was initially available in sedan or wagon form, with two or four doors. A 1960 Comet station wagon was just a Falcon wagon with different front and rear styling. The Comet version was 2.8 inches longer overall than a Falcon wagon, but shared the same 109.5-inch wheelbase as its Ford sibling.
An early Comet sedan was 194.9 inches long, 2.9 inches longer than the Comet wagon and over a foot longer than a Falcon, and it rode a 114-inch wheelbase, 4.5 inches longer than the Falcon sedan.
All of the Comet sedan’s extra length was behind the rear seat — compare the space behind the rear door cutouts in the above photos — giving 7.9 inches more rear overhang than the Ford. This tail stretch added a little bit of rear luggage space, but no more passenger room. More importantly for Ford, this approach let the four-door Comet sedan use the same doors as the Falcon, modified with different window frames and the chrome trim strip.
Structurally, the early Comet was almost identical to the Falcon except that the side sills and rear side rails were a little longer and the rear axle and springs were shifted 4.5 inches towards the rear. Front and rear springs were somewhat softer, and the Comet sedan was 93 lb heavier than the equivalent Falcon.
The Comet had one significant structural difference: a new rear powertrain mount, which bolted onto the front rails.
In the earliest Falcons, the rear mount was attached to the bridge-like crossmember just ahead of the transmission tunnel. This had turned out to transmit too much powertrain vibration and harshness into the tunnel and floorpan.
The Comet approach was better, but still not adequate, so as a running change in mid-1961, both Falcon and Comet switched to a third design, this one again mounted on the crossmember, but with a cantilevered quarter-elliptical leaf spring attached through an insulator, which was supposed to absorb powertrain vibration before it was transmitted to the body structure. Both cars retained this new mount through 1965, but it was NVH problems like this that eventually led Ford to switch its bigger unit-body cars to perimeter frames, which were much easier to isolate.
Fairlane and Meteor
Both the early Falcon and the early Comet were quite successful, and for a while, they managed to lure a lot of domestic buyers away from small imports. For 1962, Ford followed up with the midsize Fairlane and Mercury Meteor, which were aimed less at imports than at the popular Rambler Classic. The Fairlane and Meteor would offer six-cylinder engines, but they would also be available with a new lightweight V-8 engine, which Ford called the “Challenger V-8.”
The Fairlane was not dramatically bigger than the Comet, with an overall length of 197.6 inches on a 115.5-inch wheelbase. However, the need for V-8 power (and to eventually offer a hardtop sports coupe) called for significant structural upgrades compared to the existing Falcon/Comet body.
Not only did the Fairlane have a beefed-up body structure with heavier-gauge panels and more reinforcement, Ford also gave it considerably stouter demi-frame members. Ford actually described the Fairlane as “integral frame-body” rather than fully unitized — the Fairlane underbody rails were still welded to the body, but they more closely resembled a separate ladder-type frame.
Unlike the early Falcon and Comet, the Fairlane added front torque boxes between the front rails and the sills. As with the rear torque boxes used on all three cars, the front torque boxes twisted slightly in response to forces on the front rails, preventing those forces from being transmitted to the body structure. Ford engineer Forrest K. Poling explained:
As the front wheels move across uneven surfaces, the upward suspension reaction forces tend to lift the front rails. However, the front rails are welded to their torque boxes, and the tendency is for the boxes to twist or rotate rather than transmit these forces back through the vehicle. … The gauge and links of the torque box itself can be so varied as to obtain the degree of compliance that is most compatible with the balance of the structure.
Fairlane also used the front torque boxes for a new type of rear powertrain mount:
Instead of the spring-loaded mount on the 1962–1965 Falcon and Comet, the Fairlane rear mount had an insulator on a crossmember hung from the front torque boxes on two boomerang-shaped support brackets. This allowed the torque boxes to absorb some engine vibration before it was transmitted to the body.
At the rear, the Fairlane side rails were still tied together by the back support panel, but there was now a Z-shaped transverse member (which looks kind of like stairs from this angle) to provide additional strength.
In the engine compartment, the front suspension towers were still diagonally braced against the cowl, but the braces were now tubular and attached to hat-shaped mounts bolted to each spring tower.
Like the Falcon and Comet, the Fairlane and Meteor used double wishbone front suspension with high-mounted coils and lower control arms located by drag struts. The drag struts bushings were now designed with enough compliance to let them move fore and aft in response to bumps, something Ford had also done with the big Lincoln Continental.
Fairlane rear suspension was similar to Falcon and Comet, although the rear springs were longer and a bit stiffer. The rear axle used spring-loaded, rubber-isolated “iso-clamps” between the axle and the springs so that the rear leaf springs would be completely rubber-isolated. Mercury later used similar iso-clamps for the Cougar.
The Fairlane felt more solid than the Falcon, but it was also much heavier: around 500 lb heavier, even with a six-cylinder engine.
Nearly all of the above description also applied to the 1962 Mercury Meteor, which had different front and rear styling and a longer tail that gave it 4.7 inches more rear overhang than the Fairlane. The rear springs were relocated slightly to shift the axle another inch to the rear, giving a wheelbase of 116.5 inches.
A 1962 Meteor was 203.8 inches long, 6.2 inches longer than a Fairlane. It was also 9 inches longer and over 400 lb heavier than a Comet sedan. Despite the availability of the V-8 engine, the Meteor never caught on: Comet buyers apparently didn’t think it was enough bigger or nicer to justify the higher price, and sales were slow. The Meteor was dropped after 1963.
Falcon and Comet Convertibles and V-8s
Although the structural illustrations Ford released for the early Falcon and Comet emphasized the demi-frame members attached to the floor, both cars also relied heavily on their roofs and roof pillars for structural rigidity. This made offering a convertible or even a pillarless hardtop body very troublesome: Without the added strength of the roof, the remaining structure wasn’t stiff enough without a lot of modifications.
The stouter Fairlane structure could be offered as a pillarless hardtop with no great weight penalty, but the hardtop versions of the Falcon Futura and Comet S-22, added for 1963, were over 100 lb heavier than an equivalent two-door sedans, reflecting the structural reinforcement needed to make up for the loss of the B-pillars.
Falcon and Comet convertibles were heavier still, gaining over 300 lb compared to a two-door sedan. Such weight penalties are common on unit-body cars that were not originally designed to be convertibles. If designers anticipate that a model will be available in open-top form, the body can be designed to put more of the structural loads through the floor and cowl; if that has to be done after the fact, it always weighs more than if it was part of the original design brief.
Even that reinforcement wasn’t enough to handle the added weight and torque of the 260-cid V-8, which became optional on the Falcon and Comet in mid-1963. The 260 would fit fine, that wasn’t the issue, but the heavier engine required yet more structural upgrades, plus modifications to the running gear. Since a lot of that mirrored the design process of the Fairlane and Meteor, enabling the Falcon and Comet to take the V-8 engine involved making them more like the Fairlane.
Ford offered the above illustration, whose dark areas indicate the major structural reinforcements, including heavier-gauge sheet metal, beefier sills, and incorporation of the Fairlane’s thicker front rails and front torque boxes (which the six-cylinder Falcon and Comet still didn’t have).
The V-8 Falcon and Comet also got bigger Fairlane wheel spindles, brakes, driveshaft, axle, radiator, and steering gear, plus stiffer three-leaf rear springs. The impact of all this beefing-up is best indicated by comparing the weight of the ragtop models — a 1963½ Falcon Sprint convertible was a further 300 lb heavier than a six-cylinder Falcon Sport Futura convertible.
For 1964 and 1965, Ford and Lincoln-Mercury commonized some Falcon and Fairlane parts, including some Fairlane front suspension components, but the V-8 Falcon and Comet (which could now have the Challenger 289 engine) still had substantial structural differences from the six-cylinder models. This made the V-8 cars more complicated and expensive to build. Falcon and Comet sales didn’t really justify so much complexity, especially since the V-8 versions weren’t terribly popular. Roughly half of 1964–1965 Comet buyers chose a V-8, but only 21.3 percent of 1964 Falcons and 18.3 percent of ’65s had an eight-cylinder engine.
Later Falcon and Midsize Comet
With compact sales losing ground to intermediates and the new Mustang, Ford apparently decided it was time to consolidate for 1966.
The Fairlane, Falcon, and Comet were all restyled and revamped for 1966. Rather than continuing to borrow pieces from the Fairlane, the 1966 Falcon and Comet now became variants of the latest Fairlane frame-integral body shell, differing more in sheet metal than in actual structure.
This was most obvious in the new station wagons: 1966 Falcon, Fairlane, and Comet wagons now shared a common 113-inch wheelbase and were almost the same size, with only slight differences in exterior dimensions due to their different styling.
In the Comet line, the pricier Comet Capri, Caliente, and Cyclone models were now Fairlane twins with different styling and trim, sharing their 116-inch wheelbase with Fairlane sedans, hardtops, and convertibles. The Comet had always straddled the line between compact and midsize, and the 1966 revamp made its midsize status official.
1966 Falcon sedans and coupes were now cut-down Fairlanes with a shorter nose and shorter tail. Wheelbase was reduced by 5 inches, which appears to have been achieved by shifting the rear axle and springs 5 inches forward, basically the reverse of the procedure used to create the original 1960 Comet. (Look at the space behind the rear wheel cutout compared to the same area of the Comet Caliente pictured above.) Passenger space wasn’t meaningfully affected — there were some fractional differences in headroom and hip room between the 1966 Falcon and Fairlane four-door sedans, but rear legroom was identical. A Falcon sedan was somewhat awkwardly proportioned compared to its bigger sibling, which was a foot longer, but the main practical difference was 2.9 cu. ft. less usable luggage space.
Since it was now a truncated Fairlane, the Falcon shared the heavier Fairlane structure, including its isolated rear powertrain mount and front torque boxes. (Australians had gotten front torque boxes a year earlier on the XP Falcon.) This added about 150 lb compared to the 1965 Falcon, although the lightest two-door Falcon was still 272 lb lighter than the lightest 1966 Fairlane sedan.
The Falcon Futura hardtop and convertible were both dropped for 1966. There was no structural reason Ford couldn’t have offered convertible or hardtop versions of the 1966 Falcon, since the Fairlane offered both, but Ford obviously preferred that buyers interested in those body styles step up to the pricier Fairlane 500 or 500XL (or the Mustang).
Often forgotten was the oddball Comet 202, which was almost as obvious a Fairlane-Falcon hybrid as the wagons. Unlike the Falcon, the Comet 202 rode the same 116-inch wheelbase as the Fairlane coupe or sedan, but with its own shorter nose and tail, which made it 195.9 inches long overall, 1.1 inches shorter than a Comet Capri, Caliente, or Cyclone, but almost a foot longer than the Falcon sedan. This seems to have caused more confusion than actual interest, and the Comet 202 was dropped after only two years.
All three cars now shared a common suspension, with various minor changes for greater isolation, although the basic layout remained the same.
The Fairlane-based Falcon expired at the end of the 1969 calendar year, but the nameplate continued for the rest of the 1970 model year on a renamed base Fairlane.
Fairlane/Torino and their Mercury counterpart (now called Montego/Cyclone) survived with further restylings through 1971.
For 1972, the Torino and Montego switched from integral frame-body to perimeter frame construction, also abandoning the high-mounted front coils and rear leaf springs. One could argue that the original Falcon/Comet platform had effectively ended in 1965 — the 1966–1971 cars, even the Falcons, were more directly related to the 1962 Fairlane/Meteor than to the old Falcon — but the ’72 intermediates shifted decisively in a different direction. (The original Falcon continued for much longer in Australia and Argentina.)
“But what about the Mustang? What about the Maverick?” I hear you saying. Those are also part of the Falcon lineage, but for reasons of length, I’ve split those into a separate upcoming post.
Related Reading
Vintage Motor Life Review: 1960 Ford Falcon – The Resurrection of the Model A (by Paul N)
Curbside Classic: 1960 Comet – Orphan Looking For A Home (by Paul N)
Curbside Classic: 1963 Mercury Meteor Custom – It’s the Little Things That Count (by Jeff Sun)
Curbside Classic: 1963½ Ford Falcon Futura V8 – The Economy Compacts Enter The V8 Era (by Paul N)
That was really interesting to a techno-geek like me.
It perfectly demonstrates how mass and anti-rationalisation can run away with you once you start changing things.
And how the well-designed Falcon started off almost like a large, albeit rationalised European car before rapidly evolving into a behemoth.
I can see soo much Cortina in those early designs.