Pete05
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- Melbourne, Australia
The 'Great Race' as it is known today, began as the 'Armstrong 500' for stock standard sedans at Phillip Island in November 1960. Back then, the race was for locally manufactured or assembled cars only, imports were not eligible. It was held at this circuit for 3 years until changing venue to Bathurst and it's date to the October long weekend for 1963. Whilst one EK was entered in 1961, and a lone EJ in 1962, the old 'Grey-motored' early models couldn't keep pace with the competition in those years. But 1963 was altogether different, with the new 179 'Red-motored' EH 'S4'. The Scuderia Veloce entry of Brian 'Yogi' Muir and Spencer Martin was the fastest qualifier for that year, edging out the more nimble factory team of Ford Cortina GTs. In the early days of the Great Race, cars were classified in groups according to their retail price and were started off the grid in these groups; hence there was no 'Pole Position' or 'Outright Winner' as such. The Muir car dropped a tailshaft and eventually finished ninth. However, a private entry in the hands of Morgan & Sachs claimed second.
The EH 225 179M-S4, to give it it's official title, was Holden's first 'toe in the water' exercise into production racing. Many myths exist about Holden's first 'Sports car'.
There were no disc brakes, wide wheels, suspension mods, multiple carburettors or floor shifts. When the EH series was first released, the previous US 'Grey Motor' (or Sideplater) was replaced by the new 149ci and 179ci 'Red Motors'. The larger 179 was available only with GM's Hydra-Matic automatic. Holden's 3-speed manual box, basically unchanged from the EJ, wasn't up to the task. There was, however an upgraded gearbox in the planning stages and the S4 was used to trial the new stronger gearbox. It was still very similar to the old box, having the same ratios and synchromesh only in second and third gears. The clutch was increased in diameter, as was the tailshaft.
Aside from slight carburettor alterations (to suit the manual drivetrain) and the removal of the transmission cooler from the radiator the S4's engine was standard issue 179. The only modifications to the cars worthy of note were the upgrading of the brake shoe retaining springs, the enlarging of the fuel tank from 9 to 12 gallons and the addition of a PBR VH24 vacuum booster to the brakes as standard equipment. A manual version of the 179 was made available across the entire EH range in early 1964 utilizing the new 'box, clutch and tailshaft, but without the brake mods and the bigger tank.
One interesting S4 item was the more comprehensive toolkit. This was brought about by one of the Armstrong race rules, which stipulated that all work on the car, for the first half of the race was to be carried out only by the driver and using only the tools provided in the car's toolkit. This applied whether the car broke down around the track or in the pits.
Research into some of these cars has shown that a certain amount of factory 'blueprinting' was carried out. Greater than usual care was taken with sizing and assembly of many components. Cylinder heads were chosen for their more even casting in the port and combustion chamber area, so as to have same size for each cylinder and to be closest to the maximum available compression ratio. Blocks, pistons, conrods and crankshafts were also picked for matching machining, weights and sizes. Suspension components came in for similar treatment, all springs, coils and leaves were chosen at the maximum end of factory tolerance and front control arms and uprights were precisely measured to attain the desired alignment specs, once again at the required end of factory tolerances.
GMH only built around 120 S4s to cover the racing requirement for proof of a minimum 100 identical vehicles sold and registered to the public, making them reasonably scarce and highly collectable.
http://www.ehholden.com.au/infpage/ehspec.htm
http://holdenpaedia.oldholden.com/EH_Technical_Specifications
http://members.tripod.com/~sixties_holdens/ehhist.html
http://www.uniquecarsandparts.com.au/holden_EH_technical_specifications.htm
http://www.uniquecarsmag.com.au/new-and-reviews/article/articleid/77429.aspx
http://en.wikipedia.org/wiki/Holden_EH
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