GM 2300 engine

The 2300 was a 2.3 L/140 in³ (2287 cc) straight-4 automobile engine produced by General Motors from 1971 through 1977. The Vega engine, as it became known, was unusual for the time with an aluminum block and cast iron SOHC head.

"Road & Track" reported at the time that this highly-anticipated engine was "a letdown" and "extremely rough and noisy". In addition, an advanced feature of the engine was the fact that it did not have cast iron cylinder liners. Instead it used silicon impregnated into the aluminum. This design has now become very common. Unfortunately inadequate coolant flow and problems with the jackets sometimes resulted in warping of the engine block and subsequent oil burning. GM changed the coolant pathways for 1975 and then the engine's name to Dura-Bilt in 1976 to declare that its problems had been resolved.

It was available with a 1 or 2 barrel carburetor and was used in the Chevrolet Vega and similar Pontiac Astre, and the later Chevrolet Monza and its H-body siblings: the Oldsmobile Starfire, Buick Skyhawk, and Pontiac Sunbird.

The 2-barrel version, known as the "L11" option, also included a hotter camshaft for a power increase of 20 hp (15 kW). The engine used a 3.501 in (89 mm) bore and 3.625 in (92.2 mm) stroke and 8:1 compression.

Cosworth

A Cosworth version of this engine was produced in 1975 and 1976. It was a version of the 2300 de-stroked to 3.16 in (80 mm) with special DOHC 16-valve heads and solid lifters. It produced 120 hp (89 kW) and 107 ft·lbf (145 N·m).

ee also

* GM engines
* GM H platform