HYDA Duratec ST — the five-cylinder heart of the Mk2 Focus ST

The second-generation Ford Focus ST marked a major change in Ford's hot-hatch formula. Instead of the naturally aspirated four-cylinder used by the earlier ST170, the Mk2 ST adopted the HYDA 2.5-litre turbocharged inline-five, producing 225 PS at 6,000 rpm and 320 Nm from just 1,600 rpm. Ford's workshop specifications confirm the HYDA engine code, 2,522 cc capacity, 83 mm bore, 93.2 mm stroke and 9.0:1 compression ratio.

Its five-cylinder layout is a major part of the ST225's identity. The uneven firing character, strong low-end torque and distinctive exhaust note gave the Mk2 Focus ST a personality completely different from the four-cylinder hot hatches around it.

The HYDA also forms part of Ford's broader 2.5-litre turbo five-cylinder performance family, which was subsequently developed further for the 305 PS Focus RS and 350 PS RS500, though those cars use the separate JZDA engine code. Ford's parts catalogue lists HYDA and JZDA separately while showing substantial component-family overlap between the ST and RS engines.

This GasketKeys piece recreates the distinctive five-cylinder head-gasket profile as a compact stainless-steel tribute to one of the most recognisable engines of the modern Fast Ford era.

Engineering & Craftsmanship

• Industrial Grade Build: Precision laser-cut from premium 304 stainless steel with a durable brushed-metal finish.
• Protective Frame: Housed within a 3.3 mm CNC-machined PLY frame for protection and presentation.
• Technical Precision: Cylinder bores, coolant passages and major gasket features are digitally mapped from the original gasket geometry.
• Letterbox Friendly: The slim under-5 mm packaging format keeps UK delivery straightforward.

Those construction points follow the product framework supplied in your MD file.

A subtle tribute to the ST225

The Mk2 Focus ST has developed a particularly strong enthusiast identity in the UK. Its appeal comes from more than the ST badge: the turbocharged five-cylinder engine is the defining characteristic of the car.

Rather than conventional logo-based merchandise, this keychain represents the engineering underneath the bonnet. It works particularly well as a memento for an ST225 owner, previous owner, modifier or someone rebuilding one of these cars.

5. Technical Specifications