What size engine is in the 1977 Pontiac Grand Prix?
The 1977 Pontiac Grand Prix was powered primarily by a 400 cubic-inch V8, with a 455 cubic-inch V8 available as an optional upgrade on higher-trim models.
Engine options in the 1977 Grand Prix
In 1977, the Grand Prix offered two large-displacement V8s in the U.S. market. The following are the core options you would typically find for most configurations of that year.
- 400 cubic-inch V8 (6.6 L) — standard engine on most 1977 Grand Prix models.
- 455 cubic-inch V8 (7.5 L) — optional upgrade on higher-trim models or with certain packages.
Notes: Exact availability could vary by trim level and production date. The 400 cu in V8 served as the baseline for most configurations, while the 455 cu in V8 represented the more powerful option for buyers seeking extra performance.
Performance context
During the late 1970s, emissions regulations and fuel-economy considerations influenced engine performance. The 400 V8 offered solid performance for its era, and the 455 V8 provided additional power where customers wanted it, within the constraints of federal rules at the time.
Summary
In summary, the 1977 Pontiac Grand Prix was built around two primary V8 sizes: a standard 400 cubic-inch engine and an optional 455 cubic-inch engine for higher-trim or package-equipped models. This lineup reflected Pontiac’s approach in the era to balance performance with tightening emissions and fuel-economy standards.
