USA vs USA — 1984 vs 1965
| Grand National GNX | Riviera Gran Sport 425 | |
|---|---|---|
| Horsepower | 276 hp | 360 hp |
| Torque | 360 lb-ft | 465 lb-ft |
| Engine Size | 3,791 cc | 6,965 cc |
| 0-60 mph | 4.7 sec | 7.2 sec |
| Top Speed | 125 mph | 130 mph |
| ¼ Mile | 13.4 sec | 15.3 sec |
| Weight | 3,500 lbs | 4,500 lbs |
| Wheelbase | 2,743 mm | 3,073 mm |
| Length | 5,059 mm | 5,410 mm |
| Units Produced | 547 | 3,961 |
| Original MSRP | $29,290 | $4,424 |
| Value (Excellent) | $300,000 | $95,000 |
| Collectibility | 10/10 | 8/10 |
| Rarity | 9/10 | 7/10 |
It's a closely fought contest. The 1984 Buick Grand National GNX brings quicker acceleration, lighter weight, greater rarity to the table, and the 1965 Buick Riviera Gran Sport 425 answers with more power, higher top speed, better value. Both are excellent machines that reward their owners in different ways — there's no wrong answer here.
Buick has long offered a diverse lineup, and comparing the 1984 Buick Grand National GNX with the 1965 Buick Riviera Gran Sport 425 highlights the breadth of the marque's engineering philosophy. The 1965 Buick Riviera Gran Sport 425 holds a clear advantage in raw power with 360 hp compared to 276 hp, a 84-horsepower difference that shapes the driving experience. Under the hood, the contrast is notable: the Buick Grand National uses a V6 OHV Turbocharged (Buick 3.8L) displacing 3,791 cc, while the Buick Riviera relies on a V8 OHV (Buick 425 Nailhead) with 6,965 cc. In the sprint to 60 mph, the 1984 Buick Grand National GNX edges ahead at 4.7 seconds versus 7.2 seconds. The Buick Grand National carries a weight advantage, tipping the scales 1000 lbs lighter. Rarity plays a significant role here — with only 547 units built, the 1984 Buick Grand National GNX is considerably scarcer than the Buick Riviera's 3,961 examples. On the collector market, the 1984 Buick Grand National GNX commands a significant premium over the 1965 Buick Riviera Gran Sport 425, reflecting differences in prestige and rarity. From a collectibility standpoint, the 1984 Buick Grand National GNX rates higher among enthusiasts and auction houses.