Pontiac began work on a V8 configuration in 1946. This was initially intended to be an L-head engine, and 8 experimental units were built and extensively tested by the end of the 1940s. But testing comparisons to the OHV Oldsmobile V8 revealed the L-head could not compete performance-wise. So, in addition to building a new Pontiac Engineering building in 1949–1951, the decision to re-direct the V8 to an OHV design delayed its introduction until the 1953 model year, however the Buick division was introducing its new engine (Nailhead V-8) in 1953 and asked the corporation to hold back or delay Pontiac's V-8 introduction until the 1955 model year which it did.