DOHC - Tuning for performance
Across the Sierra model range, there are generally speaking three types of “tunable” engine: the OHC 'pinto', the DOHC 16v Cosworth and the 12v V6.
That is to say, having been involved in motorsport to some degree or another, each of the engines can be tuned relatively easily due to an abundance of knowledge and tuning accessories.
The 8v DOHC engine used from late 1989 onwards is somewhat different.
Although it typically has good torque delivery and otherwise excellent potential, it has largely been ignored by tuning companies – the engine was never used widely in motorsport due to the success of the Cosworth 16v platform, and as a consequence is not seen as very tunable.
Ford's perception of the engine from the outset didn't help it's reputation amongst tuners - it is believed by some that Ford only ever intended it as a low maintenance, smooth running, economical, motorway mile muncher rather than a source of massive automotive power, brought in as a replacement for the ageing OHC 'pinto' engine to meet tougher emissions laws.
Indeed, if driven sensibly on a long motorway journey, fuel economy figures of between 40 and 45 miles-pergallon can be realized quite easily from a well maintained car and it is perceived to be a more refined engine than the 'Pinto' it replaced. So refined that Ford still produce and fit the engine (albeit in 16v form) in 2.0 and 2.3 capacities to their Galaxy MPV today.
Because the 8v DOHC is largely ignored by tuners, the options for simple “bolt on” upgrades are fairly limited.
However, with a bit of thought and careful tweaking using available tuning components, very respectable and useful power gains can be had by following the guidelines contained in this How To...
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