The cylinder bore is 77.0 mm (3.0 in) and the piston stroke is 72.0 mm (2.8 in), the compression ratio rating is 8.3:1. The GX670 engine produced 24 HP (17.7 kW HP) of horsepower at 3,600 rpm and 50.8 N·m (5.18 kg·m, 37.5 ft·lb) of torque at 2,500 rpm. General information Cylinder Block and Head. Location. California, USA. Nov 4, 2008. #1. As many here are aware, Honda's older 4 cylinder car engines rotated "backwards", that is, clockwise instead of counter-clockwise when viewed from the rear (flywheel side). (I hope I got that right). This means the engines were mounted transversely with the accessory side of the engine against the.