IF WE accept that the car has been around for nigh on 100 years, then Danish engineer Ralph Miller's 1947 theory of improving on the efficiency of the conventional, internal combustion engine is relatively new technology.
Miller, born in 1890, went to the United States in 1915 and was involved in various areas of engineering, working for a number of employers including Ingersoll-Rand and the American Locomotive Company.
While employed by the Nordberg Manufacturing Company of Milwaukee, Wisconsin, Miller was granted a patent for a device which 'varied the final combustion temperature in four-cycle internal combustion engines'.
But it was not until the early Eighties that Mazda developed Miller's idea of delaying the closure of the intake valve in order to reduce the compression ratio without detracting from the all-important expansion ratio, or power stroke.
By 1990, Mazda's R&D department had sufficiently perfected the so-called Miller-cycle theory and a new, highly efficient 2.3-litre V6 engine was put into production.
It is this engine which powers the top-of-the-range Eunos 800M. Eunos, Mazda's luxury arm, currently comprises three models: the 800, the slightly smaller 500 and the top-selling sports coupe Eunos 30X.
The 800M, with its unique Miller-cycle engine, performs like a three-litre model with, says Mazda, the economy of a two-litre. But technical advances apart, the 800M is a superb car and a casual observer would probably be unaware of any differences under the bonnet.