Sport auto: Two tyre tests in one, and two victors

German car magazines love a tyre test, and sport auto is the latest to publish its findings on a batch of the current summer products. Using a Toyota GT86 as test vehicle, the performance-oriented sister publication to auto motor und sport evaluated seven size 225/40 R18Y UHP tyres together with three road legal semi-slicks. In consideration of their different focus, the trio were separated from the seven UHP products in the final results table.

The UHP tyres tested by sport auto were the Bridgestone Turanza T001, Continental SportContact 5, Goodyear Eagle F1 Asymmetric 3, Kumho Ecsta PS91, Michelin Pilot Sport 4, Pirelli P Zero and Toyo Proxes Sport, while the semi-slicks under scrutiny were the Michelin Sport Cup 2, Pirelli P Zero Trofeo and Toyo R888 R.

Michelin’s Pilot Sport 4 was the undisputed winner in the UHP tyre category. The sport auto testers found it to offer “fantastic feedback, stable driving characteristics and outstanding grip in the wet” and “excellent stopping qualities in both the wet and dry.” The only shortcoming the testers mentioned was a slightly elevated rolling noise. The Michelin tyre gained a total average score of 9.3 points (from a maximum of ten) and was rated ‘highly recommended’.

An average total score of 8.9 points secured the Goodyear Eagle F1 Asymmetric 3 second place. According to sport auto, the Goodyear tyre was “direct and agile in the wet” and “good-natured with a short braking distance on dry asphalt.” Weaknesses mentioned included its reaction to change of load in the wet and an only moderately sporty dry handling behaviour. The Eagle F1 Asymmetric 3 was rated ‘recommended’, as were the following four tyres.

Two from the four – the Bridgestone Turanza T001 and Continental SportContact 5 – finished with a total average score of 8.6 points. The first of these was judged to provide decent wet grip with very good lateral control and dynamic handling characteristics, as well as a wide limit range on dry road surfaces. The Continental tyre demonstrated “very safe lateral control in the wet” as well as a high level of aquaplaning safety, short stopping distances in the dry and balanced, precise handling. The testers marked the Continental tyre down, however, for comfort and external noise, and the Bridgestone for “indirect, not so sporty steering response” on dry surfaces, as well as longitudinal aquaplaning.

Finishing just behind the pair with 8.5 points was the Pirelli P Zero. The sport auto testers found the tyre to have a short stopping distance in the dry and precise behaviour with reliable lateral control in fast curves, however the Pirelli rubber was marked down for its wet braking result as well as load change response in the wet.

Next finished the Toyo Proxes Sport with an average total score of 8.2 points. The Toyo tyre was criticised for its “indifferent driving behaviour on wet and dry surfaces” and its “sparse cornering grip in the wet.” On the other hand, the Proxes Sport delivered the shortest wet stopping distance of the seven and offered good traction and decent resistance to aquaplaning.

The Kumho Ecsta PS91 finished the UHP test in seventh place from seven with a total average score of 7.7 points, having been marked down for wet precision and handling, a certain nervousness in the dry and poor ride noise. With this score, the Kumho tyre only qualified for a ‘still recommended’ rating. On the plus side, it gave balanced performance in the dry and delivered a good result in the aquaplaning test.

The sport auto test clearly demonstrated that semi-slicks aren’t suited to wet road surfaces, and the magazine’s editors are critical of their use in the rain. Yet the very qualities that make them unsuitable for wet driving give them sporty performance in the dry, and therefore the candidate tyres were scored from a maximum of twelve points in these disciplines rather than ten. Furthermore, the three test categories – wet, dry and environment – were differently weighted than for the UHP tyres. This meant that the P Zero Trofeo, the highest scoring of the three semi-slick tyres, received a total of 9.3 points, however would have only received 7.7 points had the points been tallied in the same way as for the UHP tyres. A decisive factor in the Pirelli semi-slick’s victory was its “superior steering precision on the circuit” and good traction, as well as fast lap times. The Pirelli tyre was closely followed by the Toyo R 888 R, which the sport auto testers found to have a comparably short stopping distance in the wet. The primary advantage offered by the Michelin Sport Cup 2, on the other hand, is its broad range of applications, however on the track it didn’t quite compare with the uncompromisingly designed Pirelli and Toyo models.