Wings for Subaru Impreza GD

A rear wing is an inverted aerofoil that presses the rear tyres onto the road as speed rises. The wings here are model-specific, for the boot lid or tailgate, in factory and sport styles, including a version with a third brake light.

Air passing under the curved lower surface of the wing travels faster than the air over its top, so the pressure underneath falls and the wing is pushed down. Doubling the speed roughly quadruples the downforce, and the drag that comes with it. More angle of attack gives more load and more drag, until the flow separates and the wing stalls.

A wing works in clean air, which is why it stands on pedestals above the body rather than lying on it. Rear downforce on its own shifts the balance rearward, steadying the car in fast corners but adding understeer, so a front lip or splitter usually goes with it.

Check three things when choosing:

• Model and body: each wing is listed for one model and its years, as boot and tailgate shapes differ.
• Brake light: if a wing would hide the factory high-level light, the car still needs a working one in view. One version here has its own built in.
• Material: polyester laminate is stiff and repairable, but needs filling and priming before paint.

Bolt the wing through the lid with spreader plates underneath, as the load at speed and the leverage of the pedestals can crack a thin panel. Seal each hole against water, then connect the brake light to the factory circuit and test it. Check that the gas struts still hold the heavier lid open.