Firestone unsure how softer tires will respond to Watkins Glen pace

IndyCar teams traditionally do not practice on the alternate compounds, saving them for qualifying, and as a result Firestone is as much in the dark as the teams, regarding the softer rubber’s behavior this weekend at Watkins Glen.

Harrigle told Motorsport.com: “We brought reds [soft alternate compound tires] for the [mid-June] test but we’re already considerably faster than we were even then, so I honestly don’t know what performance advantage or wear rate we can expect to see compared with the black tires.”

The resurfacing work at Watkins Glen International since IndyCar last raced here in 2010, and the huge downforce of the aerokit-equipped DW12s compared with the previous-generation IR09s, have seen practice laps some five seconds under the lap record. But that has not yet provided a clear indicator regarding the tires’ performance compared with other road courses.

Barber Motorsports Park is so abrasive on tires that in qualifying the reds peak for one lap, whereas at Mid-Ohio, there is a plateau of some three laps before they lose their ultimate grip. Harrigle said he did not know which of these characteristics the would be seen at Watkins Glen.

“Until we see some laps on the reds, I don’t have a good answer as to how they’ll respond.  We’ll find out along with all the teams in qualifying.

“But this is a very severe place on tires. A 146mph average speed means it’s the fastest road course we run at. And this is the hardest compound road course tire we’ve used in 2016. It’s unique to this track.

“It’s the same tire construction that we use on other road courses, such as Mid-Ohio or Road America, but this is the hardest compound.”  

Graining on rears

Despite the extreme grip from the track surface, the cars’ downforce, and the fact that the DW12 tends toward understeer – a speed-killer in the long duration turns at Watkins Glen – Harrigle said that so far the rear tires have been taking the most punishment. 

“We are seeing some graining on the rear tires,” he said, “which I expect to go away as the track rubbers in from more laps going down. The tires being asked to accelerate the cars so hard in one of the complexes here is what is putting so much energy through the rear tires.”

Harrigle said that so far, the teams have not dabbled in extreme setups that would cause uneven wear across the tires.

“The teams tested here a couple of weeks ago, and we tested here in June,” he commented, “but as I said, the conditions have changed considerably since then. So the teams have so far this weekend been working on setups, going through their ranges to see where they want to be. We haven’t seen anything extreme that would wear one part of the tire excessively over another.

“They all responded well to our recommendations following the tests. We’ve actually gone up a little bit on pressures due to the high average speeds around the track and I believe all teams have followed those recommendations.”