XYZ Racing Circuit Master Coilovers — Opel KADETT C 1973-1979

The Kadett C’s competition career started before most current circuit regulars were born. The GT/E homologation variant built a following that hasn’t faded in five decades, and the OP04 platform still appears at historic meetings across Europe – light, rear-wheel drive, and responsive enough to expose poor setup choices within the first few corners. The Circuit Master is XYZ Racing’s track-specification coilover, built not for occasional spirited road use but for the sustained demands of timed sessions where consistency across multiple runs matters more than any single fast lap.

Running a car of this era at competitive pace is a specific discipline. The hardware has to match the intent, and the Circuit Master was developed precisely for that kind of circuit work.

What this coilover does for your 1973-1979 Opel KADETT C

On a car as light as the Kadett C, geometry management carries exceptional leverage over handling balance – ride height and spring rate changes register immediately in how the platform behaves through direction changes and under braking. The Circuit Master’s three-knob system produces 9,720 distinct damping combinations across rebound, compression, and height, which means circuit-to-circuit and session-to-session adjustments are genuinely granular rather than notional. Height adjustment operates independently of damping, so altering corner weights does not disturb the damping characteristic you have already established. For a Kadett C competing in historic class – where engine output is fixed by class regulations – that degree of setup precision is a direct performance resource.

About the Circuit Master

XYZ Racing’s Circuit Master sits at the peak of their competition hardware range, alongside the Drift Spec and Tarmac Rally configurations. It is a monotube damper series developed and validated by XYZ racing teams at international circuits worldwide, with no concession to road-use compromise in its specification. The three-knob architecture covers compression, rebound, and ride height independently, producing 9,720 possible adjustment combinations to suit different track surfaces and tyre compounds. The small-orifice oil-passage design is a deliberate feature of this specification: under significant vertical inputs, oil is routed through a restricted channel, which can generate a brief audible note during that phase of travel. This is normal behaviour for a damper of this construction and is not indicative of a fault. The Circuit Master is designed for sealed-surface circuits where the focus is entirely on damping precision rather than road-bump absorption.

Fitment for the Opel KADETT C (1973-1979)

This kit is engineered to the Opel Kadett C OP04 platform, covering the full production span from 1973 to 1979. Confirm your build year falls within that window before ordering – the earlier Kadett B and the later Kadett D run different platform geometry and are not interchangeable with this fitment.

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Pick your ride height specification in the configurator below.