Pontiac V8 Cylinder Heads – Casting numbers and Specs

Ram Air III Pontiac Heads

Pontiac V8 Cylinder Heads.

Over the years Pontiac v8 Cylinder heads came in many specifications. Pontiac used different valves and combustion chamber size for their V8s to change compression ratios, fuel economy, and horsepower output. All Pontiac V8 cylinder heads from 1955 to 1976 are essentially interchangeable. Except for some special heads the bolt pattern, the bore spacing, and deck heights are the same.

Pontiac heads produced PRE 1968 used a closed combustion chamber design while heads produced from 1968 on used an open chamber. The high output heads produced by Pontiac after 1967 used bigger intake and exhaust valves and a 14-degree valve angle. These heads flow better producing more power than the heads produced pre-1967.

Looking for a performance head for your Pontiac?

There are aftermarket heads available but, If you don’t want to use aftermarket heads. Then the best option would be to choose a high output Pontiac heads produced from 1967 on. The 1962 and 1963 Super Duty engines would work well also. However, they are harder to find and like the 1967 heads, they have a closed combustion chamber.

Excluding the Ram Air IV and Ram Air V heads. From 1967 to 1979 Pontiac engines used the same pushrods, Rocker arm, and valve covers. From 1972 up Pontiac also changed the head’s exhaust crossover. Make sure to use the correct intake manifold. The Ram Air IV also has a taller intake port and the Ram Air V has Round Intake ports. These heads will also require special intake manifolds.

Ram Air IV Pontiac V8 Heads

Evolution and Improvements

For 1967 Pontiac increased the valve size of the high output engines. Increasing the intake valves from 1.92” to 2.11” and the exhaust valves from 1.66 to 1.77”. They also changed the valve angle from 17 to 14 degrees. This improved port flow and overall performance.

In 1968 Pontiac heads changed from a closed chamber to an open chamber design. The new combustion chamber decreased quench area and the surface to volume ratio. The new design also improved flame propagation, increasing power, and reducing emissions.

For 1971 due to new smog requirements, Pontiac reduced the compression 8.41:1 by increasing the combustion chamber CC. The lower compression reduced emissions but, at the same time robbed the engines of their incredible power.

Pontiac Heads – Ram Air V Tunnel Port

High output Pontiac V8 Cylinder Heads

• 1962 – 389 SD Code 544127
• 1963 – 389 SD Code 543797
• 1967 – 400 Ram Air or 428 Code 670
• 1967 – 400 Ram Air Code 97
• 1968 – 400 Ram Air I and 428HO Code 37” Ram Air I and
• 1968 – 400 Ram Air II Round Port Code 96
• 1969 – 400 Ram Air III or 350HO Code 48
• 1969 – 400 Ram Air III Code 62
• 1969 – 400 Ram Air IV Round Port Code 722
• 1969 – 400 Ram Air V Tunnel Port Code 44
• 1970 – 400 Ram Air III Code 12
• 1970 – 400 Ram Air III Code 13
• 1970 – 400 Ram Air IVI Code 614
• 1970 – 455HO Code 64
• 1971 – 455HO Code 191 – Low Compression
• 1972 – 455HO Code 7F6 – Low Compression
• 1973-1974 455SD Round Ports Code 16 – Low Compression

Pontiac V8 Cylinder heads – Casting location and other Info

How to find the Pontiac V8 Cylinder heads casting numbers and Production date.

Casting Number

The number is usually cast at the center or the right or left exhaust port. Some heads may have the number cast below the spark plug or below the valve cover. The casting on the outside of the head was composed of 6 or 7 digits for early heads. Later heads only used the last, the last two or last 3 digits of the casting number.
From 1973 on Pontiac also stamped a secondary head code on the machined pad just below the valve cover. This code designates the heads combustion chamber size.

Date Code

The date code is usually cast lust below the valve cover. The first letter identifies the month while the last number designates the year. The numbers in the center of the code represent the production date.

Example: D052 = April 5, 1972

Pontiac V8 Heads – Casting numbers

Pontiac Head Intake Blueprinting Specs