Fuel rejection

THERE'S no difference between the engine in the base Commodore and the S. Both have the same 3.8-litre ECOTEC V6, producing 152kW at 5200 revs and 30 Nm at 3600 revs. Holden recommends using 91 octane regular unleaded, but you could try using PULP or the higher 98 octane fuels. You might see a slight improvement in fuel economy and perhaps performance, though the cost of the fuel, in my view, would outweigh the benefits.