In the Thunderbird (and Lincoln Continental) front-wheels-only application, Ford uses a fixed caliper with dual opposed cylinders mounted to the steering spindle above and behind the wheel axis. Ford engineers have noted similar characteristics in controlled-rate stopping tests and say that this point is reached at approximately 1200 psi brake line pressure. Some rear-wheel locking and skidding occurred in the earlier stops, but as the linings and drums heated up they seemed to stabilize. The deceleration rates and stopping distances are nothing short of phenomenal for a 5000-1b. (actually less than 0.5 G but there was quick lock-up of the rear wheels upon slowing past 70 mph: it was necessary to release pedal pressure momentarily to bring the car under control.Īs can be seen in the table, the new 'Bird's disc/drum braking system gets stronger and firmer as it is used-and the harder it gets used the quicker it stops the car. The second stop recorded a maximum deceleration of 18 ft. sec., quite substandard in our view and below the average of all recent domestic cars tested. Maximum reading on the CL decelerometer: 17 ft. serious fade was evident before the car had slowed to 65 mph: all pedal feel was lost and by the time velocity had dropped to 25 mph, the right rear shoes were grabbing and locking, forcing the car to skid sideways. While perhaps a bit unfair in view of the rarity of such treatment in normal service, the procedure has teen used by CL as a criterion by which to rate ultimate stop-ping power. The "crash stops" are made at the end of acceleration runs in each direction, a matter of only a minute or so apart and hardly space enough to allow the drums to cool down. Results of the usual braking test, i.e., two all-on stops from 80 mph, with a similar '64 model, are quite enlightening and elevate the newly-braked car into proper perspective. The real interest insofar as the new model is concerned lies in the caliper-disc braking system and its effect on the woefully neglected area of stopping performance. Nonetheless, the data panel illustrates the present 'Bird's level of performance. Frontal area of the latter was 22.1, com-pared to the present car's 22.5 sq. and terminal speed but it would be interesting to determine the relative difference between the new body and the old. Aerodynamics hardly play a part in this car's e.t. That the new 'Bird improves on such performance is most likely because of the different tire size (8:15-15 low profiles) and apparent attention on the part of the engineering staff to reduction of operating friction. quarter-mile time, attaining 72 mph at the quarter marker. Regular readers will recall it returned an 18.7 sec. less and had exactly the same engine /transmission / rear axle equipment, although it was mounted on 8.00-14 wheels. Save for the brakes, there have been no significant mechanical changes between '64 and '65, either-or for that matter since the '62. has satisfied itself with only a slight re-arrangement of decorative bright work to serve as the visual indicator of the new model year. That test car, a convertible with the then-available fiberglass tonneau cover and wire wheels, has been superseded by the newly-dressed 'Bird which displayed its angular lines for the first time last fall. A case in point is the Thunderbird, which Car Life editors last reported on in the July 1962 issue. ONE THING ABOUT a stable car design: There's not much point in putting one of the models through road test procedures every year or so.
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