Power-assisted front disc brakes were now standard across the Falcon range. The GT variant of the XB also included four-wheel disc brakes (the earlier GT/GT-HO models used large finned drums at the rear). The first 211 XB GTs built were fitted with a US-built version of the Cleveland V8 engine known as the 'big port', and later XB GTs were fitted with an Australian-built version of the engine with 'small port' heads and a 4-barrel 605 CFM downdraught Autolite 4300 carburetor, rated at @ 5400 rpm and @ 3400 rpm of torque. The twin driving lights remained, as did the bonnet locks. The bonnet scoops of the GT were now integrated into the "power bulge" on the bonnet, the bumpers were now body-coloured, and the power bulge, wheel arches, sills, and valances were painted in a contrasting colour to the body colour (usually black, but dependent upon the actual body colour choice).