Re: Top Speeds

Posted by su8overdrive On 2023/2/16 23:08:59

Thanks, Acolds, for this better than usual conjecture, if still just that. Most of the torque peaks sound close, but the blown 288-ci Cord's, despite from the usually stringent Autocar, seems a mite optimistic, and the rpm too high, 260 ft. lbs./2,200 rpm would be closer. The fourth gear ratio is also off. Should be 2.95:1, a trace lower than the unblown Cords' 2.75:1 since superchargers like rpm.
The Cord's top speed is also inflated, since Cord engineers themselves could wrest an all out 108 mph at Bonneville.

The Packard Twelves certainly put out more torque than in the 1961 guestimates above. Jan. P. Norbye ascribed 348 ft. lbs. at 1,200-1,400 rpm for the 445-ci V-12, 366 at the same rpm for the 473 Twelve. But then in his book, "The 100 Greatest American Cars, 1904-78," Norbye claims in selection #89, the 1947 Packard Super Clipper, a top speed of 110, which is a bit generous, probably prompted by the alleged 110 mph of a '41 Buick Century with Compound Carburetion and rare, no-cost optional "Economy Rear Axle" of 3.6 instead of usual 3.9:1 at the GM Proving Grounds, which you know Flint engineers tweaked to the nines.

Some may wonder why this of interest to some of us gearheads. Simply, the higher the genuine top speed, the more relaxed cruising, which brings us back to CCR's concern.