With the outbreak of WWII Napier needed to expand its engine production facilities as part of the war effort. Acton Vale to the west of London was considered to be a vulnerable site so, by the end of October 1939, the decision was made to build a shadow factory on the East Lancashire Road on the outskirts of Liverpool.
In 1940 some essential engineering staff were moved from Acton Works to Liverpool to oversee the building and equipping of the new machine shops, assembly areas and test facilities. All told the floor area covered over 1 million square feet and was ready for production by the end of 1941 employing a freshly trained precision-engineering trained workforce.
The first fully tested Napier Sabre II engine to emerge from Liverpool Works was delivered in February 1942. This was only 13 months after Acton's own first production Sabre II. By 1942 the total DNS workforce exceeded 10,000.
Post war the now English Electric owned Liverpool site became the main production factory. In 1950 the site took on the full production of Napiers engine turbocharger products reaching 2,000-plus units per annum by 1966. Similarly in the early 1950's the site was responsible for the production of the Deltic engine. Alongside this EE Co. also produced domestic appliances.
Napier Research Station
Also constructed on the site from 1947 to 1953 was the Napier Research Station (NRS). This large and well equipped part of the business was constructed by EE and Napier in order to provide a uniquely powerful test and development facility for the new axial comressors and turbines being designed into new aero gas turbines at the time. The intention was to install sufficiently high steam turbine-driving power to accomodate compressors up to any foreseeable size enabling them to be tested and analysed. This was for in-house use and customers.
The NRS had three blocks; centrally placed were offices for administration, test unit design and research data analysis. To one side was a block containing the Gas Turbine Plant for development work, a machine shop and an instrumentation shop. In the block on the other side was a complete Yarrow Steam Turbine Compressor Plant removed from a Hunt Class Royal Navy Destroyer, with two 300 psi superheated steam turbine drives of 10,000 hp. These could be linked together to provide 20,000 hp at up to 20,000 rpm when required.
Netherton Works, also on the outskirts of Liverpool / Bootle was built about 1951. It did sub-contract production of Rolls Royce Avon engines which, reputedly, had such high build standard that the engines were more powerful than those produced by RR. Netherton also did quite a lot of the Napier Turbo Blower work. Some other English Electric work was done there too including some large hydro-electric components. It was also the 'home' of the Deltic Prototype locomotive, which entered the works on a spur-line built for the purpose.