The Nordec R10 and RG10 racing engines were manufactured by the North Downs Engineering Co. (Nordec) of Whyteleafe in Surrey, a little to the south of London. The main business of this firm related to automobiles, but in mid 1948 they entered the model racing engine field as a sideline.
The engines were offered in both spark ignition and glow-plug forms. They were designed by Nordec's chief designer and works manager, the well-known control-line speed flier John Wood. Their design was based very closely upon that of the highly successful 1946-48 version of the famous McCoy 60 model from the USA, albeit with some significant structural modifications.
The Nordec engines were built to the very highest standards and could be tuned to deliver quite reasonable performances by knowledgeable owners. The legendary tuner and later engine builder Fred Carter enjoyed considerable success with a Nordec which he modified himself. However, the advent of the Dooling 61 and the vastly improved McCoy 60 Series 20 completely overshadowed the Nordecs in performance terms, rendering them obselete almost as soon as they became available. The company made several brave and at least partially successful attempts to upgrade the engines' performance, but the small size of the market for large racing engines in Britain eventually forced the cessation of production in mid 1950.
A great deal of additional information about the Nordec engines can be found in my earlier article on Ron Chernich's "Model Engine News" (MEN) web-site.