The 454 Coolstyle models were the final 'end of the run' models that were produced.
As the production of the 454 were coming to an end they 'ran down'/ran out of various
parts, and they substituted the disc braked rears with the drum brake rears that they
were still fitting to the Mitsi Colt.
(Both vehicles at the time were built on the same production lines in the same factory)
Other items such as the Colt heater controls also found there way into these 454's,
and even (if I remember correctly) the lower powered non-variable valve timed engines
that were fitted to lower CZ1 range of Colt models were fitted into the Coolstyle 454's.
These engines were the 1.1, 1.3, and 1.5 petrol engines.
Both the non-variable and variable valve timed engines used the same engine block
casting (for each partiuclar size, obviously), machined to the same bore and stroke,
and they even look the same at first glance, but they are not !
The difference is that the variable valved timed engines have an additional small opening
machined into the top left on one side of the engine block, and that is necessary to
fit/mount the additional components that work to achieve the variable valve timing.
There is no simple way to convert or to add those components to the engine to enable
them to be brought up to the same level of power as the variable valve timed engine.
In addition, the existing wiring loom might not have the additional wiring for this, and/or
the ECU might not have the necessary progamming coded into it to enable it to operate
the variable valve timing even if the additional components were fitted.
I have driven a 1.3 Colt with and a 1.3 Colt without variable valve timing, and the most
noticeable difference is that the latter is somewhat flat né gutless when accelerating.
