Holden V8 engine

In 1964 Ford and Chrysler in the US released V8 versions of their respective Falcon and Valiant models which Holden expected to soon be released in locally assembled or produced versions. In response, in January 1965 the company's engineering division initiated a forward engine program review and concluded that by 1969 a V8 option was a necessity for Holden, with forecasts of 35 per cent of all Holdens sold in 1970 to be V8s, rising to 50 per cent by 1975. Initially six capacities from were planned over a 12-year life cycle, but early in the design phase this was reduced to just two, an 'economy' 253ci (4143cc) and an enlarged 'performance' 308ci (5044cc) version, which became known as the 4.2L and 5.0L respectively. Design targets of a weight of , which was lighter than equivalent US engines, and a net output of and at 4000rpm and at 2400rpm were set for the 308, which was mechanically identical to the 253 except for a larger bore and bigger pistons, along with heavier counterweights on the crankshaft to compensate for the increased reciprocating mass. Originally an alloy inlet manifold was specified to reduce weight, but this was changed to iron when problems were encountered in the casting process. The exhaust manifolds were also cast iron but the timing case cover remained as an alloy item. The initial pre-production engine was the 253, which not only met but greatly exceeded the design targets. The complete engine assembly from fan to flywheel and all auxiliaries weighed in at 460 lb, around 12% less than the design target, while net output for the higher compression (9.0:1) version fitted with a 2-barrel carburettor was with 262 lb.ft of torque, which matched or exceeded the targets set for the larger 308. The design was also very compact with a width of 22 inches, and was only 80 lb heavier than the straight six, but producing over 40% () more power than that engine in standard form. The first running engine was delivered in October 1966. Unfortunately, the engine failed after just four days testing from a seized oil pump; however, the problem was found to be caused by swarf residue rather than a fault in the design or the quality of the components. Further testing proved that the engine was smoother and more durable than Holden's six cylinder, no mean feat as the 186 was considered a smooth and reliable engine in its day. The new engines were initially intended to be offered as part of the 1968 Holden HK range, but production issues caused the project to run behind schedule and consequently 307ci Chevrolet engines imported from Canada were used instead. Initially the 283ci engine was to be used but it was replaced in North America for the 1968 GM model year with the 307ci engine - this engine was used instead for HK. GMH had already planned to use the 327ci Chevrolet engine in the HK GTS327 and it would have originally been fitted in the HK range alongside 253 and 308 if things had gone as planned. The 253 made its public debut in the Holden Hurricane concept car at the 1969 Melbourne International Motor Show, albeit it in a highly modified form featuring increased 10.1:1 compression, big cam and solid lifters, and producing over . The new engines entered mass production soon after in the HT model range, with the 253 being used for manual vehicles whilst the 307 SBC was retained for automatic vehicles. The 308 however debuted in the HT Brougham at the same time but as automatic only (two different imported 350ci Chevrolet engines (auto and manual versions) replaced the 327 and thus the HK GTS327 became the HT GTS350). The 253 was initially only available with a 2-barrel carburettor while the 308 was only ever available with a 4-barrel carburettor (except for when it was used in Bedford trucks in the late 70's). In 1988 fuel injection appeared for the first time on a Holden V8 engine, on the VL Commodore SS Group A produced by Holden Special Vehicles (HSV), Holden's new performance partnership with British-based Tom Walkinshaw Racing (TWR); however, this was not a standard production engine, which still continued to feature a carburettor. Later that year the VN introduced the 5000i engine with new cylinder heads and multi-point fuel injection which represented the most extensive redesign of the standard production Holden V8 since its launch in 1969. This engine continued in all subsequent Commodores until 1999 (2000 for the VS Series III Ute), when it was replaced by the US-made all-alloy Gen III LS1 5.7L V8 in the VT Series II. ==Design==

The Holden V8 is a water-cooled naturally-aspirated 4-stroke gasoline engine featuring eight cylinders arranged in a 90 degrees vee-formation. It is an overhead valve design featuring two valves per cylinder with a camshaft centrally located in the engine block above the crankshaft, driven by a timing chain attached to toothed sprockets, with the camshaft in turn driving the distributor and oil pump. Valve actuation is by hydraulic lifters and pushrods to rocker arms (roller lifters in some models) in the cylinder heads; the lifter bore angle in the engine block is 45 degrees from the block centerline. A belt-driven radiator fan and water pump are located on the front of the engine block taking drive from the main pulley, as is the alternator. The cast iron engine block features a separate pressed steel non-stress bearing sump assembly with the crankshaft located within five main bearing journals secured with 2-bolt bearing caps; 4-bolt main bearing caps featured on later performance versions. Depending upon the application, induction was either carburettor or fuel-injection (multi-point or sequential, depending on the year). For the 1986 VL Commodore, the engine was modified to run on unleaded fuel which carried forth to all subsequent models. == Applications ==

Initially offered in versions, the engines were intended to be offered as part of the 1968 Holden HK range, but the project ran behind schedule and instead became part of the 1969 HT model range. In the HT, the Holden V8 sold alongside the Chevrolet Small-Block engine until 1974 with the introduction of the HJ series. The V8 engine also appeared from 1971 in the Statesman range of large size luxury cars which Holden established as a separate marque, replacing the Holden badged Brougham. In 1974, both the 253 and 308 engines were added to the Torana range for the first time in the LH series (after an aborted attempt by Holden Dealer Team boss Harry Firth to introduce the V8 to the smaller LJ Torana range in 1972 which was stopped by the Supercar scare). The engines were also offered on the LX model range introduced in 1976, but not the final UC range which appeared in 1978. Both engine capacities were offered on the first VB Commodores which appeared in 1978. The 253 version was not available in the VK Commodore range, released in 1984, but continued in Holden WB commercials until their cessation in late 1984. In 1985, the special editions modified by Holden and their official after-market tuner, Peter Brock's HDT Special Vehicles, began introducing the version of the engine, created to slip underneath the engine capacity cut-off in Group A touring car regulations, allowing Commodore competitors to run at a lower competition weight. This slight shrinking of the traditional Holden 308 saw the Group A Commodore's racing weight drop from . Due to the complex Group A regulations, this also allowed the racing cars to run bigger wheels and tyres without any drop in power. Indeed, the VK Commodore SS Group A was one of the fastest cars in the world of Group A racing when it hit the tracks in 1986. HDT Special Vehicles also offered a more powerful version of the engine enlarged to in some of its VL models between 1986 and 1988, including the controversial Calais Director. This engine, making as much as , was an expensive option, particularly once Holden severed ties with HDT in February 1987, which drastically increased the prices of all HDT models, and consequently very few of the 5.6-litre motors were made. Bore and stroke is . 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 Holden's new performance vehicle partner Holden Special Vehicles (HSV) in partnership with British-based Tom Walkinshaw Racing (TWR). While Group A disappeared after the VN model range, the fuel injected engine, often referred to by its nickname, The Iron Lion, was offered in Commodores until the VS III Commodore utility in 2000, although there were no longer V8 VS III utilities available for sale during the latter part of 2000. HSV vehicles featured a variety of more powerful versions of the 5.0-litre, which were also available on regular V8 Holdens as part of the SV Enhanced package. Additionally, from 1994 with the VR series, a "stroker" was standard on the HSV GTS and optional on the Senator, and later on the Statesman/Caprice-based Grange from that its introduction in 1996. 253 / 4.2 L Introduced in the Holden HT alongside the 308 in 1969, later being added LH Torana in 1974 and 1978 for the VB Commodore. The 253 was dropped Torana range in 1978 with the UC Torana, it continued to be used until 1985 for the Holden WB and 1984 for the VH Commodore 304 / 5.0 L Introduced in 1985, in the VK Commodore for Peter Brock's HDT Special Vehicles, created to slip underneath the engine capacity cut-off in Group A touring car regulations, allowing Commodore competitors to run at a lower competition weight. Discontinued in December 2000 with the release of the VU Ute for Coupé utilities and June 1999 for the rest of the line with the release of the VT II Commodore and WH Caprice. 308 / 5.0 L 344 350 / Harrop Stroker HSV vehicles featured a variety of more powerful versions of the 5.0-litre, which were also available on regular V8 Holdens as part of the SV Enhanced package. Additionally, from 1994 with the VR series, a "stroker" was standard on the HSV GTS and optional on the HSV Senator, and later on the Statesman/Caprice-based Grange from its introduction in 1996. == See also ==