USA vs USA — 1957 vs 1959
| Ambassador Custom | Invicta Convertible 401 | |
|---|---|---|
| Horsepower | 255 hp | 325 hp |
| Torque | 325 lb-ft | 410 lb-ft |
| Engine Size | 5,359 cc | 6,571 cc |
| 0-60 mph | 10.5 sec | 8.5 sec |
| Top Speed | 110 mph | 118 mph |
| ¼ Mile | 17.8 sec | 16.0 sec |
| Weight | 3,502 lbs | 4,350 lbs |
| Wheelbase | 2,845 mm | 3,150 mm |
| Length | 5,334 mm | 5,562 mm |
| Units Produced | 18,842 | — |
| Original MSRP | $2,986 | $3,515 |
| Value (Excellent) | $30,000 | $85,000 |
| Collectibility | 5/10 | 7/10 |
| Rarity | 7/10 | 7/10 |
The 1959 Buick Invicta Convertible 401 emerges ahead in most objective measures, offering more power, quicker acceleration, higher top speed. The 1957 Nash Ambassador Custom counters with lighter weight, better value, but the numbers favor its rival. Still, both are remarkable machines, and the final choice often comes down to which driving experience speaks to you.
The 1957 Nash Ambassador Custom and 1959 Buick Invicta Convertible 401 stand as two of the most notable Full-size cars from Post-war. Both emerged during a period of intense competition, and choosing between them remains a passionate debate among collectors. The 1959 Buick Invicta Convertible 401 holds a clear advantage in raw power with 325 hp compared to 255 hp, a 70-horsepower difference that shapes the driving experience. Under the hood, the contrast is notable: the Nash Ambassador uses a V8 OHV displacing 5,359 cc, while the Buick Invicta relies on a V8 OHV (Buick 401 Nailhead) with 6,571 cc. In the sprint to 60 mph, the 1959 Buick Invicta Convertible 401 edges ahead at 8.5 seconds versus 10.5 seconds. The Nash Ambassador carries a weight advantage, tipping the scales 848 lbs lighter. On the collector market, the 1959 Buick Invicta Convertible 401 commands a significant premium over the 1957 Nash Ambassador Custom, reflecting differences in prestige and rarity. From a collectibility standpoint, the 1959 Buick Invicta Convertible 401 rates higher among enthusiasts and auction houses.