XYZ Racing Tarmac Rally Coilovers — Mazda COSMO 13B/20B ROTARY 1990-1996

The JC-series Eunos Cosmo is one of the strangest grand tourers Mazda ever built – a 1500kg twin-turbo rotary coupé with a long wheelbase, soft factory damping and a chassis tuned for highway loping rather than tarmac stage work. Drop the standard struts and the car’s true intent surfaces: a front-engined, rear-drive platform with the 13B-REW or triple-rotor 20B-REW hanging over the nose, asking for support the OEM hardware was never designed to give.

The XYZ Racing Tarmac Rally coilover is built for that specific rebalancing job. It pulls the JC-Cosmo’s body down onto its tyres, gives the rotary’s weight somewhere to settle under braking, and replaces the wallowing factory damping with a properly valved monotube system that can take a sealed-surface rally stage or a fast B-road without falling apart.

What this coilover does for your 1990-1996 Mazda COSMO 13B/20B ROTARY

On a stock JC-Cosmo, turn-in feels delayed because the soft front springs let the nose dive before the front tyres take a real bite. The Tarmac Rally kit corrects that with stiffer linear springs and a monotube damper that controls weight transfer instead of allowing it. The 30-step damping adjustment lets you bias the car towards softer compliance for broken tarmac or firmer body control for smoother stages. Ride height is fully adjustable on each corner via the lower spring perch, which matters on a long-wheelbase coupé where corner-weighting actually changes how the rear axle puts the twin-turbo power down. Pillowball top mounts on the front sharpen steering response and let you run measurable negative camber without bushing slop.

About the Tarmac Rally coilover

This is a 30-way adjustable monotube coilover designed for sealed-surface rally and fast-road use where surfaces are imperfect but never loose. The damper body is a single-tube design with a separated oil and gas chamber, which means consistent damping force as the fluid heats up across a long stage. Spring rates are matched to the chassis and the rotary’s nose-weight, and the kit ships with adjustable lower mounts so ride height and spring preload can be tuned independently – the right way, not by collapsing the spring. Up front the kit uses pillowball upper mounts; at the rear it retains rubber to preserve some compliance over expansion joints and patched tarmac. Construction is hard-anodised aluminium for the threaded bodies, with a steel damper shaft.

Fitment for the Mazda COSMO 13B/20B ROTARY (1990-1996)

Built specifically for the JC-series Eunos Cosmo chassis (internal code MA20) covering both the 13B-REW twin-rotor and 20B-REW triple-rotor variants from 1990 to 1996. The kit is a direct bolt-on replacement using factory mounting points front and rear – no fabrication required.

What buyers also search for

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Configure your spring rates, damping preference and ride height below.