Car (South Africa)

The innovators

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TURBOCHARG­ED engines are everywhere, with all but a few automakers applying this tech to meet strict emissions laws without compromisi­ng power output or driving pleasure. Back in the day, though, this device was met with lifted brows.

Upon its introducti­on in 1961, the Oldsmobile F-85 consisted of sedan and station-wagon body styles. Later that year, two coupé variants, the Club and Cutlass, were added. Both featured a highcompre­ssion version of the fourdoor’s Buick-sourced aluminium V8 petrol sending 138 kw and 312 N.m to the rear wheels.

In 1962, cosmetic changes such as a revised grille and new interior trim were made to the F-85 line-up. The biggest update, though, was the addition of a more powerful model, the Jetfire. The uprated variant was based on the coupé and made use of the same high-compressio­n 3,5-litre V8. The Jetfire, however, was equipped with “something extra”, as one of its ads described it. Lifting the bonnet revealed a Garrett T5 turbocharg­er, making the Jetfire the first production car to use such a device.

The small-diameter turbo was developed by American aerospace manufactur­er Garrett Airesearch – now known as Honeywell – the same company which produced air-expansion cooling turbines for the Lockheed P-80 Shooting Star, the United States’ first jet airplane. The T5 unit featured an integral wastegate and had a boost capacity of 34 kpa at 2 200 r/min, which gave the standard coupé models’ naturally aspirated V8 a healthy kick. The turbopetro­l produced 160 kw (215 hp) and 407 N.m, which meant for every cubic inch, it made one horsepower. The Jetfire sprinted from 0-100 km/h in less than 10,0 seconds and could reach 177 km/h.

During developmen­t, the Michigan-based automaker was met with an array of complicati­ons; one of them being the combinatio­n of high compressio­n ratio (10,25:1) and forced induction, which resulted in spark knock when the throttle was applied with gusto. To solve this problem, Oldsmobile built a fluid-injection system spraying a mixture of distilled water and methanol on the combustion chamber to cool it and ensure the fuel burnt smoothly.

Ultimately, though, the Jetfire was a commercial failure. Only 3 765 were sold (compared with the standard model’s 33 018) and Olds soon halted production.

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