6. Pontiac Phoenix SJ
The Pontiac Phoenix SJ offered an appealing performance trim in the late 1970s, boasting sporty features and upgraded handling. However, it never received a powerful, muscle-grade engine. GM’s strategy to avoid competition with its own models—especially the Chevrolet Nova and other V8-powered siblings—meant the Phoenix SJ remained underpowered. Enthusiasts were left wishing for more muscle under the hood. For more insights on the Phoenix SJ’s restrained performance, visit Curbside Classic.