(first posted 10/28/2012) The all-new 1967 Cadillac Eldorado (CC here) was GM’s proud new personal luxury coupe and the most expensive car of its kind. The artist formerly known as The Standard of the World dazzled Americans with its knife-edge styling, front-wheel drive, 340-hp, seven-liter V8 and every available comfort and power amenity known to the fine engineers at GM.
The homely little R-10 (CC here) was an evolution of a line of very compact rear-engine Renault cars dating back some 20 years . It cost about one-fourth as much as the Eldorado, and its list of comfort amenities began and ended with excellent seats.
This admittedly specious comparison is mostly irrelevant, save for one vital aspect: Brakes and tires.
Most especially so the brakes, which obviously are among any car’s most critical and fundamental safety devices. The 1967 Eldorado came with standard drum brakes that were totally overwhelmed by the massive weight of its FWD powertrain. A Car & Driver test yielded a shocking 386-foot stop from 80 mph:
“Our Eldo test car carried drum brakes all around and managed to smoke and slew to a halt—sideways in the road—in a pitiful 386 feet…which forced one observer to ask where they [GM] found the moral justification for marketing a car that they knew was too heavy for its brakes. The question prompted a certain amount of hand-wringing and eye-rolling, whereupon they produced a heretofore unseen Eldo equipped with optional disc brakes. This car was much better—stopping in 312 feet with vastly improved directional stability—and was intended, according to Cadillac spokesmen, for the ‘performance-minded customer.’ This evidently means that the poor dolt who is not interested in ‘performance’ is also apparently not interested in being able to stop effectively…and the absence of disc brakes on all Eldorados is simply bad news, especially when the extra $100 added to the base price is relatively unimportant on an $8,000 car.”
Even 312 feet for the disc-brake version was poor performance for a new, top-tier car capable of 120 mph. But to release the Eldorado with drum brakes–a shocking failure that GM rectified in a few years–was another slice in GM’s self-inflicted, decades-long death by a thousand cuts. It’s not as though disc brakes were unknown to them; after all, the Corvette had had them since 1965 (also a few years too late).
Especially so since the Eldorado was of course heavily based on the 1966 Toronado, which shared the same drum brakes and had already been criticized for the overwhelmed front brakes.
It’s important to note that a vehicle with a large front weight bias like the FWD Eldorado and Toronado are particularly demanding on their front brakes, because of the additional weight transfer under braking, which leaves very little weight on the rear tires, rendering the rear brakes almost useless under a full panic stop.
Meanwhile, the R-10 came with four-wheel disc brakes standard. It could stop cleanly from 70 mph in 190 ft, and do so repeatedly. In a way, it’s almost overkill that the R10 had four wheel discs, since a rear engine car like it doesn’t have the weight transfer problem, and actually uses its four brakes almost equally in a rapid stop. That’s why rear engine cars like the Corvair and VW had much better braking than would be expected given their modest-sized brake drums.
In addition, the R-10 was shod with Michelin X steel-belted radials, as most French cars had been for well over a decade. There’s no need to enumerate the vastly superior handling, safety and durability of radials, but Detroit didn’t begin to take them seriously for almost another decade.
Why no discs and radial tires, GM? Too expensive? Maybe a call to Renault would have been in order.
(Postscript: please note that the point of comparison is brakes and tires, not other aspects of these two very different vehicles)