Holden 253 V8

Holden 253 V8 - Australia's First Mass Produced All Aussie V8


Holden 253 V8
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The Holden 253 V8. Development of the first mass-produced All-Aussie V8 began in 1964...

The development of the Holden 253 cu. in. V8 started in 1964 when the GMH Engineering Department began a serious study for the design of the next Holden engine. The V8 configuration was chosen because it met all the requirements for compact size and light weight. It gave increased displacement over the six cylinder range without loss of smoothness and the potential for future displacement and output increase.

Following design studies which showed that GMH could satisfactorily combine the best features from world practice suitable for Holden in Australia, in a package, smaller and lighter than then equivalent displacement engines already in production, six experimental engines were built for evaluation in 1966.

A full production program was then undertaken, aiming at the provision of a smooth, powerful, durable and economic engine.The result was the first Australian V8 for volume passenger car use. The engine had a displacement of 253 cu. in., 4.146 litres, a compression ratio of 9:1, a maximum horsepower 185, and a maximum torque of 262 lb. ft. Dry weight of the complete engine assembly from fan to flywheel and with all accessories including the alternator and starter was 460 lb., only 80 lb. heavier than the light weight six cylinder engine. The overall width was only 22 inches.

The V8 was tested and proved in extensive dynamometer and road durability testing at the GMH technical centre and proving ground. Its development was aided by its inclusion as the power unit for the GMH research car the Holden Hurricane. The cylinder heads incorporated cross flow porting and large valves in a shallow wedge shaped combustion chamber for good breathing, conducive to a high specific output. The cylinder block of 3.625 cylinder bore was a compact iron casting and together with the cylinder heads, was cast in GMH foundries.

The nodular iron crankshaft of 3.06 stroke was extremely rigid due to the short stroke and large diameter main and connecting rod journals. Optimum engine balance was obtained by close weight control of pistons, connecting rods etc., and by individual balance of crankshaft, flywheel and clutch, followed by a dynamic balance determined on the completed engine assembly when running under its own power.

Piston and piston ring specifications were developed to provide quietness, long life and low oil consumption. The valve train represented the first use in Australian manufacture of a design incorporating stable cylindrical aluminium rocker arm pivots in conjunction with pressed sheet metal rocker arms. As in 6 cylinder engines, GMH manufactured hydraulic lifters were used, incorporating a long plunger travel to allow the use of the non-adjustable rocker supports. Camshaft drive was by roller chain, with neoprene damper on drive side.

From 1971 the 253 was fitted to the Statesman and, in 1974, the engines were added to the new larger LH Torana range and was offered as well on the LX model range, but not the final UC range which appeared in 1978. Both engine capacities were offered on the first Commodores which appeared in 1978. The 253 ci version was dropped in 1984 and was not offered in the VK model range. At the same time the special editions modified by Holden's official after-market tuner, Holden Dealer Team began introducing the 304ci (4.9 litre) version of the engine, created to slip underneath the 5000 cc engine capacity cut-off in Group A touring car regulations, allowing Commodore competitors to run at a lower competition weight.

Fuel injection replaced the carburettors initially on the VL Commodore SS Group A SV, again with Group A touring car racing in mind, this car produced by replacement after-market tuner Holden Special Vehicles (HSV). While Group A disappeared after the VN Commodore, the fuel injected 304 engine was offered in Commodores right up until the VS III Commodore utility.