What Engine Did The 1964 Pontiac Grand Prix Have & How Much HP Did It Produce?

Pontiac developed its first Grand Prix for the 1962 model year. By the time 1964 strolled around, it was Pontiac's third best-selling car. Despite the 1964 model not yielding as much popularity as its 1963 sister, it was still a popular car. The Grand Prix was a sleek yet muscular car, providing a stylish ride for drivers going to and from work. You might not find the 1964 Grand Prix on the cheap, but there are still a few cheap and reliable Pontiacs you can get today, despite the brand being out of business. 

Part of the Grand Prix's appeal was its engine. While the Pontiac GTO was best known for running the 389 engine, one of the best engines ever put in a Pontiac muscle car, the Grand Prix also housed it. The 389 debuted in 1959 and is seen as a significant contributing factor to the rise of muscle cars in the '60s. Pontiac offered multiple configurations for cars with the 389 V8, one of which made a splash in the 1960 NASCAR season. The Grand Prix was no different. Buyers could get their 1964 Grand Prix with a two-barrel carburetor configuration, four-barrel, or the Tri-Power three two-barrel configuration. However, those who wanted better performance out of their Grand Prix could get their model with Pontiac's 421 engine.

The 389's horsepower

The power output of the 1964 Grand Prix varied depending on the engine and transmission configuration. The base model with a standard transmission produced 306 horsepower. However, buyers could also select a non-standard transmission if they liked. They had the option between the popular Hydra-Matic or the Synchromesh transmissions.

If a buyer opted for a Grand Prix with the Hydra-Matic transmission, it produced 303 horsepower. However, there was a Hydra-Matic model that only had a two-barrel carburetor, limiting its horsepower to 267 at 4,200 rpm. The Synchromesh transmission offered varied performance as well. The 389 engine with a Synchromesh transmission produced either 235 or 255 HP with a low compression ratio of 8.6:1.

As stated, those who wanted better performance from their Grand Prix could have Pontiac's 421 engine installed, which produced between 350 and 370 horsepower. The high output model of the 421 put out 460 lb-ft of torque, improving the Grand Prix's acceleration from those with the 389, letting drivers show up to work with speed and style. The 421 engine was the one that won some races in 1961 at the Pomona, California Raceway. So, the 1964 Grand Prix might have looked like your typical commuter car, it was rated to win a race or two if the driver was so inclined.