6. 1973 Pontiac Firebird Trans Am SD-455
The 1973 Pontiac Firebird Trans Am SD-455 is a legend born from scarcity and unmatched performance.
Fewer than 300 were produced, making it one of the rarest and most sought-after Firebirds ever built.
The Super Duty 455 engine offered exceptional power, cementing its status as a high-water mark for Pontiac muscle.
At recent Mecum Auctions, SD-455s in top condition have fetched between $130,000 and $180,000.
Its place in Pontiac history is secure, often viewed as the last true muscle car before emissions restrictions changed the landscape forever.