These negotiations were concluded in April 1963 with Rolls - Royce Ltd taking a 51 % controlling interest .
THR became a subsidiary of Rolls - Royce Ltd     , Diesel Engine Division , Shrewsbury .
These negotiations were concluded in April 1963 with Rolls - Royce Ltd taking a 51 % controlling interest and THR became a subsidiary of Rolls - Royce , Diesel Engine Division , Shrewsbury .