AN OLDSMOBILE RIVIERA

Concurrently, Oldsmobile management was also facing another challenge: the Ford Thunderbird. The posh four-seat T-Bird actually outsold the comparably priced Oldsmobile Ninety-Eight by a fair margin and had a distinctive style and identity that no contemporary Oldsmobile could match. Oldsmobile’s closest rival was the new Starfire convertible, but that was essentially just a dressed-up Super Eighty-Eight. To really compete with the T-Bird, Oldsmobile needed a car with a unique body not shared with mundane models.

Oldsmobile had recently lost an internal competition for Ned Nickles’ XP-715 design, which subsequently became the Buick Riviera. Stylist Dave North, then in the Oldsmobile studio, says that almost as soon as the contest was over, Olds management began pushing for a Riviera-like specialty car of their own.

Such a specialty car seemed like another good candidate for front-wheel drive, if only for economic reasons. Interior space was not a major priority in that segment, but personal luxury cars were considerably less price-sensitive than compacts were. Furthermore, erstwhile Thunderbird buyers were more likely to be open to mechanical novelty than were shoppers looking for a cheap economy car. (In fact, Ford had considered introducing front-wheel drive on the 1961 Thunderbird for similar reasons.)

By mid-1962, former Chevrolet general manager Ed Cole, now group vice president of the Car and Truck Group, decided that Oldsmobile should indeed have its own personal luxury car, along with Cadillac. Aside from the obvious market potential of such cars, Cole was looking ahead to the next-generation Riviera. The 1963 Riviera body shell, known in GM parlance as the E-body, was not shared with any other car, which meant higher unit costs. Having Oldsmobile and Cadillac share that body shell would make all three cars much more profitable to build.

It appears that Cole was less sanguine about front-wheel drive, a configuration that he had considered and discarded during the development of the Chevrolet Corvair (albeit for different reasons). However, he didn’t veto the idea outright. Around this time, Oldsmobile chief stylist Stan Wilen overheard Cole discussing FWD with Styling VP Bill Mitchell in terms that sounded at least encouraging.

THE FLAME RED CAR

Coincidentally, a few months earlier, Wilen had asked his group to come up with concepts for a new Oldsmobile specialty car. This was not a production project, and there was no specific platform or configuration in mind; Wilen later explained that it was just a way of letting the stylists stretch their creative faculties a bit between duller, more routine projects. This stress-relieving exercise yielded a number of interesting concepts, the most notable of which was a striking full-size rendering by Wilen’s assistant David North of a vivid red car against a black backdrop.

The car depicted in that rendering was not a completely new design. North, who had previously been in the Pontiac studio, says he originally conceived the sporty coupe while on loan-out from Pontiac to Advanced Studio 3, envisioning his concept as a future Pontiac. North’s sketches and scale model of the design had greatly impressed Pontiac chief stylist Jack Humbert and stylist Irv Rybicki, former head of the Oldsmobile studio, and had helped to earn North his promotion to assistant chief stylist of Oldsmobile.

North’s “flame red car,” as it was subsequently dubbed, continued to make a strong impression. A few weeks later, when Ed Cole and Bill Mitchell told Wilen that Oldsmobile would be getting its own specialty car, Wilen showed them North’s rendering, which they both loved. It was selected as the basis for subsequent design development.

Soon afterward, Wilen was ordered to scale up North’s design to the dimensions of the Buick Riviera so that the new car could eventually share the Riviera’s E-body shell. This was a controversial decision; North had conceived the design for a future version of the new intermediate A-body shell (the first version of which would be introduced for 1964), and Metzel, Beltz, and Mitchell all felt that would be a more appropriate size.

Hoping to illustrate the point, Mitchell ordered the development of a full-size clay model of an A-body version of the design. To limit interference, he took the unusual step of pulling the project from the Oldsmobile studio and sending North’s design — and North himself — back to Advanced Studio 3 (then headed by Ed Taylor and future GM Design VP Wayne Cherry), which was off-limits to all but a select few.

This stratagem failed to sway Ed Cole. The final decision was one of economics, not aesthetics: the tooling costs for the A-body were already shared by four divisions, while the Riviera then stood alone. Oldsmobile’s specialty car would have to share the larger E-body.

Major size alternations can be disastrous to a design, but Wilen ultimately felt — and most subsequent observers have agreed — that North’s concept translated surprisingly well to the bigger platform. A full-size clay model of the scaled-up design, now designated XP-784, was presented for management approval in February 1963 and approved for production (with a few additional revisions) in April. For all the stretching and tweaking, the final XP-784 still looked remarkably similar to North’s original concept.

THE UNITIZED POWER PACKAGE

Although Oldsmobile’s FWD test mules had traded the aluminum Rockette engine for the 394 cu. in. (6,460 cc) Rocket V-8, they had still mounted their engines transversely. Now that there was a chance the FWD package might need to be shared across divisions, Beltz and Watt switched to a more orthodox longitudinal engine layout, presumably to more easily accommodate other engines. While the big Oldsmobile V-8 fit transversely, fitting the all-new V-12 the Engineering Staff was then developing for Cadillac (tentatively slated to debut in Cadillac’s E-car) would not have been so easy, and contemporary GM inline sixes would have been troublesome.

The switch to longitudinal engine mounting required some rethinking of the prototypes’ dual chain drive, which we can’t imagine had been terribly efficient in any case. Oldsmobile considered turning the engine 180 degrees and mounting it behind the transaxle, à la Citroën or the old L’Universelle concept, but according to engineer Frank Ball, that arrangement was deemed unacceptably bulky. At Beltz’s suggestion, Oldsmobile engineers Howard Kehrl and Jim Lewis, who developed the final powertrain layout, instead opted to offset the engine slightly forward and to the right (by 1 inch/25mm and 1.8 inches/46 mm respectively) and mount the transmission and differential flush against the left side of the block.

The transmission itself, known in production as the TH-425, was based on the recently introduced three-speed Turbo Hydra-Matic (TH-400), used the same internal ratios and variable-pitch stator as other TH-400-equipped Oldsmobiles, Buicks, and Cadillacs. However, the gearbox was separated from the torque converter, turned 180 degrees (which also required reversing the directions of its internal gear rotation and clutch engagements), and offset to the left. The differential, a compact planetary unit developed by Buick, sat at the front of the gearbox, driving the front wheels through unequal-length halfshafts. The engine was raised 1.5 inches (38 mm) and the oil pan was reshaped to allow the longer right halfshaft to pass beneath the sump. Raising the engine also required the use of a lower-profile air cleaner and intake manifold to fit under the low hood.

The TH-425 transmitted power from the torque converter to the gearbox input shaft via a length of Morse “Hy-Vo” silent chain, 2 inches (51 mm) wide with a developed length of 46.5 inches (1,181 mm). The use of the chain raised many eyebrows — even among the engineers of Borg-Warner’s Morse Chain division, which designed and manufactured the chain — but Watt’s group had determined that chain drive offered a better compromise between efficiency, durability, and quietness than did any other alternative, including belts or gear drive. An important move in this regard was rearranging the chain drive layout to put the drive sprocket behind the torque converter (rather than interposed between the engine and the converter, as on the early prototypes), using the converter to cushion to reduce stress on the chain; this also significantly reduced noise.

Initially, the halfshafts, jointly developed by Oldsmobile and GM’s Saginaw Division, used permanently sealed Rzeppa-type constant velocity (CV) joints at each end, but the inner CV joints telescoped, allowing the halfshaft’s length to change slightly in response to lateral forces. Interestingly, the telescoping CV joint was actually invented by Pontiac’s John DeLorean, who filed for a patent on it in 1959, and was originally intended for the rear suspension of the rope-drive Tempest, where it was supposed to reduce acceleration and braking squat. Oldsmobile used it, along with careful attention to steering geometry (including a slight negative scrub radius), to almost completely eliminate torque steer. (The telescoping halfshafts were replaced for 1967 by three-ball-bearing CV joints, which worked almost as well and cost less.) The right halfshaft also incorporated a rubber torsional damper that could twist up to 7 degrees to absorb driveline shocks and vibration.

The complete powertrain assembly, again known as the Unitized Power Package, was a marvel of packaging efficiency, taking up only a little more space than the engine itself. The entire UPP drivetrain fit neatly between the front wheels, avoiding the extreme nose-heaviness that had been a problem with some early FWD cars. The UPP also made good use of existing components. Despite its external changes, the engine itself was basically a stock Oldsmobile V-8, and the TH-425 shared many major assemblies with the standard TH-400, although its internals had to be modified to alter their direction of operation. Less happily for GM, the layout was also appears to have been covered by a Ford Motor Company patent; see the sidebar below.

Until early 1964, the UPP was still not formally approved for production — Cole and GM president Jack Gordon wanted to see if it actually worked before giving the green light. They finally assented in February, after Beltz demonstrated a UPP-powered prototype at the GM Proving Grounds in Arizona.