Conversions to the Golf 4 TDi a give an old-faithful a higher level of overall efficiency and turn a car which is fast-becoming the thinking man’s hot hatch into a vehicle of unsurpassed all-round ability. At Reef altitudes, the Golf is capable of the 0 – 100 km/h sprint in just over nine seconds and a top speed of 198 km/h.

Fortunately the basic Volkswagen mechanical package lends itself very well to this kind of update. The powerplants have different injection systems, but the same basic route is used to extract more from them. Therefore, similar results will be achieved with the 1,9-litre turbodiesel fitted to many VW, Audi, and now SEAT models.

The conversions to the Golf consists of five elements - “Plug ‘n Play” Electronic Control Unit upgrade, upgraded replacement turbo, Gas-flowed cylinder head, 63 mm “catalytic converter-free” free flow exhaust system and air intake system upgrade

The end result is a meaty 125 kW, torque improving by some 18 percent to around 365 Nm. These numbers place it firmly in the upper echelon of the hot hatch class. Power swells from 81 to 108 kW, an increase of 33 percent. As the attached performance results show, effortless overtaking acceleration is a characteristic.

But none of this comes at the expense of mechanical integrity. Thanks to the SAC R&D department, we were able to properly measure and evaluate critical parameters during the R&D process. The results are quantified not only by measuring the increases on a dynamometer, but also with scientifically gathered road test results, usually benchmarked against a standard example of the same car.