Taken from a recent addition of Australian "4WD Monthly".

Following article written by Greg Brindly

Bias aside, in the 'forced induction' stakes and with turbo charging having the runs on the board, finding good reason for consideration of anything else is difficult. Indeed, to an extent it's frivolous mentioning 'super' and turbo in the same breath due to the superiority of 'exhaust induction' in most applications.

And who better to seek information from that AXT Turbo's Daryl Aston. By calling on both his and the vast experience of his staff and their many years of designing and manufacturing of quality turbo systems, the company have and continue to excel in the specialist area of specific turbocharger packages to fit only diesel engines, more often that not for 4WD vehicles. In turn, working at the coal front as a manufacturer, Daryl is acutely aware of the demands and quality requirements of turbo charging equipment and is proud to suggest that reliability is, when cared for in an appropriate manner, of the highest standard. He is also proud of the companies' 95% local content figure.

Perhaps more pertinent than AXT Turbo's success though, is the ability to dispel the old wives tale suggesting turbochargers suffer from inefficiencies including lag and excessive under bonnet heat. Indeed, for turbo diesel applications, AXT design kits which emphasise the main attributes of diesel engineering, mean torque - bags of it. Thanks to articulate design and engine matching, a turbocharger fitted to a diesel engine designed to run to a maximum of say 4500 rpm, will achieve optimum turbo boost by around 1800 rpm which is perfectly placed for towing, gentle and harsh off-road duties.

That the engine doesn't require high rpm also aids in keeping under bonnet temperatures down, and with the placement of various heat guards, the slightly increased radiant heat from the turbocharger is normally not a problem.

Also pertinent is the false suggestion that supercharging suffers less lag than turbo charging, that it provides a greater power output, reduced combustion chamber and under bonnet temperatures. The simple truth is that a supercharger is a mechanical device driven by the crankshaft, hence an inherent loss of power in driving it. Supercharging also relies on engine revolutions for its own speed and boost levels - exactly the same applies with a turbo except that as exhaust gasses are used to drive it, no initial losses are incurred to be recovered later.

Contrary to the popular belief that turbo charging increases under bonnet temperatures, with AXT's exclusive use of oil and water cooler Garret turbochargers, these keep under bonnet temperatures to a minimum.

That a turbocharger is often more compact, offers a similar power improvement, has a proven long lasting record of accomplishment and doesn't suffer or incur and mechanical maladies, is enough reason to look at equipping a diesel powered 4WD vehicle with a 'matched' system. In addition, the cost is normally somewhat less than supercharging, and yet the results are similar if not better. The icing on the cake though is that the driving experience is improved to such an extent you will wonder why it's taken you so long to make the decision.

A massive improvement in torque, hence throttle response, more power for overtaking and no struggling when towing all adds up to making the driving experience of a turbocharged diesel powered four wheel drive so much better. For further details, contact AXT Turbo on (03) 9793 7740