PPG Gearboxes dominate the most punishing rally

Cars fitted with Pfitzner Performance gearboxes dominated in last weekend's Transchaco Rally in Paraguay, an event that is regarded as the most punishing of its kind in the world. The first three cars in this gruelling three-day event were all fitted with PPG dog gear sets, whilst another four behind them meant that seven out of the top ten finishers - all of them driving Mitsubishi Lancer Evolution Xs - were equipped with PPG gearboxes.

This year saw the 40th running of this South American classic that has a reputation for its tough and torturous character. Indeed, the 3000km route contains what is regarded as the most difficult stage on the planet: Rivarola, a 60km encounter over a dust-ridden and semi-destroyed road near the Bolivian border. Understandably, there is immense credibility for just finishing this event, with the winner subsequently regarded as a national sporting hero.

Starting and finishing at Pozo Colorado in Central Paraguay, the first day saw competitors embark on 12 fast and demanding stages of the type found on the Safari Rally, with some of the straights seeing cars flat out in top gear for minutes on end! Crews then headed north for day two, where the terrain changed character and presented a further nine stages that were more reminiscent of the Dakar Rally rather than an event that is contested by cars derived from production models.

For those that had made it through the previous 48-hours of mechanical torture, there were another eight stages to contend with on day three, many of them a repeat of those covered on day one. Then, to add a final sting in the tale, the last of the event's 29 stages was a biblical 70.25-mile run – almost in a straight line – that took crews back to Pozo Colorado for the finish.

With an event as arduous as this, teams had to ensure they fitted components that would take the punishment of the 1000km of un-surfaced special stages. These components included a temporary cage that was fitted around the car for certain sections in order to deflect overhanging trees and anything else that might inflict external damage, a modification that visibly underlines the extreme nature of the Transcacho Rally.

Further adding to the demands on the cars and the crews is the issue of dust. Consequently, drivers try to use the clutch as little as possible, in order to avoid a build up of dust and debris between the driven plate and the surface of the flywheel that would eventually lead to failiure. This means that, other than traversing road sections or starting and finishing a stage, all gear changes during the competitive sections are carried out without activating the clutch.

Whilst this method of gear selection can put a strain on many transmissions, PPG's dog gear sets feature a unique tooth profile design that provides positive and effortless engagement. Added to this is the company's patented heat treatment process during production, which results in extremely strong and durable gears that will withstand the severe conditions in which they have to operate.

The leading three cars on this year's Transcacho Rally were all R4 Class Mitsubishi Lancer Evolution Xs fitted with PPG dog engagement gear sets, two of them having 6-speed sequential activation. As well as its durability, PPG's sequential transmission provided an additional benefit, by virtue of its high ratio sixth-gear. This enabled the cars to reach much higher speeds than those fitted with a conventional five-speed dog gearboxes.