- 86,854
- Rule 12
- GTP_Famine
Mazda has always sought to do things its own way - not only did it persist with the rotary engine for 20 years, but right now it can be found completely eschewing the industry trend for small capacity, blown engines in favour of more tractable naturally aspirated units - and the Xedos 9 was yet another one of the company's unique take on things.
First, the Xedos 9 was a very rare attempt at a Japanese executive car - built to take on the BMW 5 Series and Mercedes E-Classes of this world. You can count these on the fingers of one knee and the successful ones are even rarer - more so in North America with the Toyota Camry, but just about every other one of the rare attempts (Nissan QX, Mitsubishi Debonair, uhhh...) had failed to that point.
Secondly, the car was intended originally as the flagship to a new Mazda sub-brand, Amati. Japanese brands were having a bit of an identity crisis at the time, from which we got Infiniti (Nissan), Acura (Honda) and Lexus (Toyota), but Mazda was fiendish for it. Alongside the Autozam (compact & sports), Eunos (sports) and Efini (luxury sports) brands - some of which also inexplicably sold Citroens - with which Gran Turismo fans will already be aware, it had planned a full luxury brand named Amati. This brand was to sell the cars that eventually became the Xedos 6 (Amati 500), Xedos 9/Millenia (Amati 800) and the large, RWD Efini MS-9/Mazda Sentia (Amati 1000), but the venture failed at the last minute even after the dealerships had been fitted out for it.
But the most interesting part of the Xedos 9 is the engine...
Although the platform was unique to the Xedos 9, it used the classic Mazda K V6 engine range you could find in other Mazdas of the time. The little K8, a 1.8 powering the Mazda MX-3, was the first of the units. The KF was a 2.0 version, present in the 323, Xedos 6 and, in Europe only, this Xedos 9. The majority of Xedos 9s worldwide used the 2.5 litre KL variant, also found in the Ford Probe and Mazda MX-6 amongst others - but it's the flagship engine that holds the interest.
Only barely related to the rest of the range - by pretty much the engine block - was the 2.3 litre supercharged Miller Cycle engine, the first and for a time the only Miller Cycle engined car in the world and one of only three ever made.
The conventional petrol engine cycle - the Otto Cycle - is suck-squish-bang-blow. In the first part of the cycles the piston travels down the cylinder with the intake valve open to suck in the fuel-air mix, while in the second the piston travels back up the cylinder with the valves closed to compress it ready for ignition. The Miller Cycle deviates from this slightly, by allowing the intake valve to remain open for a full 50% of the piston's upward stroke. Why doesn't the fuel-air mix get driven back out? There's a supercharger keeping the intake pressure higher than the cylinder pressure!
What's the purpose of this then? Well, the fact that the piston's expansion stroke is twice the length of the compression stroke means that the thermal efficiency of the engine - the amount of energy expended squashing the fuel compared to the amount extracted by exploding it - rises, increasing fuel economy. The net result was that the 2.3 Miller produced more power and torque than any other K Series V6 (up to 230hp and 230lbfft depending on emissions equipment) to pull the 1.7 ton Xedos 9 to 60mph in around 7 seconds and cruise at 34mpg on the motorway, despite a pigiron automatic gearbox. It was still a Mazda though and could shuffle through a handling course in a manner that would surprise the unwary - Mazda claimed that the Japanese market Millenia with the optional 4 wheel steering could out Elk-test the Nissan Fairlady Z...
Though the car was originally introduced in 1993, the 1998 facelift made a few improvements - largely to the slightly stunned front end - and since I owned a 1998 car, that's the one I want!
Oh, here's mine:
Your marketing of the car caught me!
