THE Astra Convertible shares its engine with the SRi hot-hatch, as well as the Zafira mini people-mover. It's a 2.2-litre Ecotec four-cylinder unit of all-alloy construction with double overhead camshafts and four valves per cylinder, which develops 108kW of power at 5800rpm and 203Nm of torque at 4000rpm using premium unleaded fuel (95 RON). The recommended fuel is regular unleaded or 91 RON, although Holden does not quote power and torque figures for the engine on that fuel rating. In comparison, the standard 1.8-litre Astra engine produces 90kW and 165Nm on 91 RON or 92kW and 170Nm on 95 RON fuel. Fuel consumption figures for the Astra convertible, measured with the roof up, are 9.0L/100km city cycle and 5.8L/100km highway cycle for the manual transmission. In the auto those figures rise to 9.5L/100km and 6.2L/100km respectively.