Specifications
Compression on the "eight" started at 5.7 - 1 initially, and was increased to 6.2 - 1 ratio in 1934. In 1940 it was increased again to 6.5 - 1. From 1952 to 1954 two compression ratios were specified, 6.8-1 with syncromesh (manual) transmission, and 7.7-1 ratio with Hydra-Matic (automatic) transmission. The engine had a remarkably low idle speed of a 450 rpm with standard transmission and 375 rpm (while in drive) for the automatic; a modern engine is usually tuned to a minimum 600-700 rpm. The electrical system was a 6-volt primary with a negative ground, and a conventional mechanical ignition, with the firing-order 1-6-2-5-8-3-7-4. The Pontiac engines employed a full pressure oiling system, unlike its cousin the Chevrolet.
Below are specifications as per the model year and displacement.
Read more about this topic: Pontiac Straight-8 Engine