Proving its tread: BRIDGESTONE TURANZA GR-90
Just a couple of weeks after announcing that it will be pulling out of the hugely popular racing sport (for which it was the exclusive tyre supplier) after the 2010 season, Bridgestone was hosting a bunch of 40 motoring journalists from over eight Asian countries to test its brand new premium touring tyre – the Turanza GR-90.
The setting was Bridgestone`s Thai Proving Ground, a sprawling riding test centre spread over 130 acres that has been designed to simulate every conceivable type of road condition. The proving ground and the Bridgestone / Firestone Training & Communication Centre, are located right next to Bridgestone`s Nong Khae Plant near Bangkok, Thailand.
The new Turanza GR-90 is being rolled out globally in most of the markets that the company is present in, but the location and the plans for the tyre testing event had a lot to say about the current prospects for the luxury car market in this part of the world.
Track testing
The new Turanza GR-90 is Bridgestone`s new line-up of ultra-luxury tyres with the focus being high ride comfort, smooth road handling and low noise characteristics. The GR-90 is suitable for European and Japanese luxury cars and will be available in a wide variety of sizes from 14-inch to 20-inch, including low-profile versions.
The new tyre will replace the existing GR-80 and as a natural fall-out the track testing that Bridgestone had organised at the Thai Proving Ground was aimed at giving us a feel of the difference in performance and ride quality that the GR-90 delivers.
The cars that were shod with the new and old tyres and offered for our test drives were Toyota Camry and the previous generation Mercedes-Benz E-Class models. We rode the cars over a multi-purpose test pad on which Bridgestone engineers had incorporated a slalom course, a deep turn and a lane-changing manoeuvre for us to get a feel of the new tyres performance during tight cornering and high-speed turns.
The other tests that we put the new tyres through included high speed driving at speeds of about 180 kmph on the main oval-shaped circuit that is about 3.3 kilometres long and a wet surface performance evaluation by testing the tyres on a special wet.
Tech-talk
Before getting into the track performance, here is a bit about the technology that has gone into the GR-90. To achieve its objectives of reducing noise, improving ride comfort and increasing grip and performance, the GR-90 incorporates two new technologies.
New, more advanced noise reduction grooves with side branches help dissipate the usual whistling noises that are caused by straight grooves. The new inclined and L-shaped branch grooves also minimise disturbing high frequencies that lead to vibration and higher in-cabin noise.
Also, in addition to the use of a higher percentage of silica in the new tyre`s compound to reduce rolling resistance, Bridgestone`s GR-90 developers have also employed another unique technology. A new asymmetrical tread pattern has been used for the new tyres. The inner and outer side walls are shaped differently, with straight grooves being placed on the inner side to further minimise noise. The asymmetrical sidewalls are also said to deliver better straight-line travelling dynamics and minimise random external forces caused by uneven and undulating roads.
All the grooves in the GR-90 feature ribbed walls for improved water dispersion and the larger blocks located on the outer side improve the durability of the tyre and help deliver better driving stability.
To prove that the new tyres performance, especially in under standard conditions lead to hydroplaning when used tyres are used, we also tested the new GR-90 after the cars in which they were shod had put over 40,000 kms on their odo. Noise and comfort parameters were also tested by driving over a specially prepared half-kilometre road surface that simulates bad, bumpy road conditions.
The track tests proved beyond doubt that the new GR-90 has pushed the benchmark for comfort and performance in this tyre class. While noise levels on the straights and overall road grip on wet and dry tarmac has clearly improved compared to the outgoing GR-80 tyres, the improvement, though evident, was less pronounced on bad road conditions.
The new GR-90 is meant to be a premium touring tyre positioned at the top-end of the Turanza brand`s products and opposite the high-end Potenza sporty performance tyres. For aftermarket fitment, the new Turanza GR-90 can be considered by owners of the Toyota Corolla, Innova and Mitsubishi Lancer Cedia for 15-inch rims, Toyota Camry, Honda Accord, Hyundai Sonata Transform and Mercedes-Benz C-Class and Audi A4 for the 16-inch and the 17-inch and 18-inch tyres will fit cars such as the Mercedes-Benz E-Class and S-Class and the Audi A6.
Bridgestone`s Turanza GR-90 will be available at brand stores and large format tyre stores across India from this month.
handling circuit.
Bridgestone Turanza GR-90
