USA vs USA — 1968 vs 1970
| AMX | AMX 390 Big Bad | |
|---|---|---|
| Horsepower | 315 hp | 325 hp |
| Torque | 403 lb-ft | 425 lb-ft |
| Engine Size | 6,393 cc | 6,391 cc |
| 0-60 mph | 6.6 sec | 6.6 sec |
| Top Speed | 125 mph | 130 mph |
| ¼ Mile | 14.3 sec | 14.4 sec |
| Weight | — | 3,300 lbs |
| Wheelbase | 2,388 mm | 2,794 mm |
| Length | 4,450 mm | 4,877 mm |
| Units Produced | 6,725 | 4,116 |
| Original MSRP | — | $3,395 |
| Value (Excellent) | $75,000 | $65,000 |
| Collectibility | 5/10 | 8/10 |
| Rarity | 6/10 | 7/10 |
The 1970 AMC AMX 390 Big Bad emerges ahead in most objective measures, offering quicker acceleration, higher top speed, stronger collectibility. The 1968 AMC AMX counters with its unique character, 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.
Tracing the evolution of the AMC AMX from 1968 to 1970 offers a compelling look at how automotive design and engineering progressed. These two variants showcase the changing face of AMC. On paper, the two are remarkably close in power output, with the 1968 AMC AMX producing 315 hp and the 1970 AMC AMX 390 Big Bad delivering 325 hp. Under the hood, the contrast is notable: the AMC AMX uses a V8 OHV 16V displacing 6,393 cc, while the AMC AMX relies on a V8 OHV (AMC 390) with 6,391 cc. In the sprint to 60 mph, the 1970 AMC AMX 390 Big Bad edges ahead at 6.6 seconds versus 6.6 seconds. From a collectibility standpoint, the 1970 AMC AMX 390 Big Bad rates higher among enthusiasts and auction houses.