Like most American automobile manufacturers, Pontiac relied on the straight-6 design for their circa-World War II automobiles.

1930s

In the 1930s, Pontiac introduced their "multi-cylinder" engine, the 208 in³ (3.4 L) straight-6.

208

The 208 in³ (3.4 L) 208 straight-6 was produced in 1935 and 1936. It was a side-valve design with a timing chain, as was popular at the time.

Pontiac/GMC

Just as was done with their later V8s, Pontiac shared their mainstream straight-6 engine with GMC for truck use. It was also a side-valve engine, and used a timing chain. Pontiac used this engine from 1937 through 1954, while GMC only used their 223 in 1938.

222

The 222 in³ (3.6 L) straight-6 was only used in Pontiac automobiles.

223

The 223 in³ (3.7 L) straight-6 was only used in GMC trucks.

239

The 239 in³ (3.9 L) straight-6 was only used in Pontiac automobiles.

215 OHV

In the mid-1960s, Pontiac revived their straight-6 for a short time. Although it was of a different displacement, this Pontiac engine was based on Chevrolet's Generation 3 straight-6.

215

The 215 in³ (3.5 L) straight-6 was produced in 1964 and 1965. It is sometimes confused with the 215 aluminum V8 used in the two years prior. It was an OHV/pushrod engine design, quite different from the previous Pontiac straight-6 engines.

1960s OHV

Another OHV straight-6 design was adopted by Pontiac the year after the 215. This was a redesigned Chevrolet Straight-6 available in the Pontiac Firebird and the Pontiac Tempest. This version was produced from 1966 through 1969(?).

This engine was available initially in 1966 as a base motor for the tempest lemans cars and had 165 BHP (123 kW) 230 in&sup3 (3.8 L) until 1967. With the Sprint Option it produced 207 BHP with 10.5:1 Compression and a Quadrajet carburetor.

In 1968 and later the engines cubic inches were bumped up to 250 in³ (4.1 L) producing the 215 horsepower (160 kW), 20% more power than the chevrolet counterpart.

The Pontiac 3.8 was a SOHC engine based on the standard 230 (3.8L) Chevrolet I6 block, putting it in the avant garde of Detroit engineering The camshaft was driven by a quiet belt instead of the usual chain, making it state of the art for the time. This engine was used on the 1967 through 1970 Pontiac Firebird while saving quite a bit of weight in the front of the car, compared to the V8 models.

Like other Pontiac engines of the era, it was not available in Canada.