Overview
The tall, long-stroke motor's vibration tendencies are helped by large rubber engine mounts. one- and two-barrel carb versions were offered. The two-barrel version, the L11 option, also included a revised camshaft for a power increase of 20 hp (15 kW). The engine used a 3.501-inch (88.9 mm) bore, 3.625-inch (92.1 mm) stroke and 8:1 compression.
Overheating is a serious concern for the engine, since the engine block is of an open-deck design, severe overheating could cause the cylinder barrels to warp and pull away from the head gasket, causing coolant leaks into the cylinders and cylinder scuffing. Maintaining oil and coolant levels is crucial for the engine. Chevrolet dealers installed a coolant recovery tank, a low coolant warning light and extended Vega's engine warranty to 50,000 miles (80,000 km) to all Vega owners. This proved costly for Chevrolet.
The 1976 to 1977 2300 engine received a new cylinder head design incorporating hydraulic lifters to replace the taper-screw valve adjusters, improved coolant pathways, longer-life valve stem seals, a redesigned water pump and thermostat, and a five-year, 60,000-mile (97,000 km) engine warranty. The engine's name was changed to Dura-Built 140.
1975 to 1976 Pontiac Astre and 1975 to 1977 Chevrolet Monza had the Vega engine as standard equipment. Monza's H-body variants, the Pontiac Sunbird and Oldsmobile Starfire adopted Vega's revised Dura-built 140 engine one year only, for 1976 and 1977 respectively.
The Cosworth Vega engine was produced in 1975 and 1976 using the 2300 engine block. The engine is de-stroked to 3.16 inches (80 mm) giving 1,994 cc (2.0 L; 121.7 cu in), with a 16-valve aluminum cylinder head, double overhead cams (DOHC), forged components and solid lifters. It produces 110 hp (82 kW) and 107 lb·ft (145 N·m) .
Read more about this topic: GM 2300 Engine