(image credit: John Loftis)
The IMSA WeatherTech season is starting to settle into it’s usual rhythm now. Two of the four major endurance races are over and one of the two street courses are done. COTA is the first natural terrain road course of the season where in past seasons, we have seen the P2-spec cars show strong pace. The smooth surface and fast turns suited the cars but this year we have a fleet of DPi cars to watch.
Tilke-drome has fast corners, slow corners and long straights. Sectors 2 and 3 include the slow Turn 1 hairpin all the way through the esses in the beginning of the track. Sector 4 includes the slow hairpin that leads onto the long back straight. Sector 10 includes the ultralong and quick right hander along with the final two corners that lead onto the front straight. It should be noted that the 2nd speed trap values should be taken with a grain of salt. The trap is located far enough down the straight that some cars are already on the brakes.
The data analysis is the usual. The fastest 20 laps from each car were taken and averaged. The sector times and trap speeds from those 20 laps were also averaged to provide the data you see below.
Comparing this year’s race to previous runnings we see much of the same. Roughly 250 miles were covered by the overall winner and about 10% of the race was run under caution. There were a handful of retirements early in the race due to contact and other issues.
GTD saw more of the usual that fans have come to expect. Of the cars that finished the race, all but 1 of them was on the same lap. Cautions did helped this but that still impressive for an endurance race. Overall we had 5 different manufactures in the top 5 fastst laps. The Porsche from Alegra Motorsports, which has been the surprise of the year in the IMSA paddock, went quickest but was closely followed by the #75 Mercedes, #96 BMW, #48 Lamborghini and the #86 Acura. The Mercedes and Porsche seemed to have a slight advantage through the esses while the BMW M6 had some legs down the straights. Overall the entire class was within 1.4 seconds on average lap time and within 2.5 mph through the first speed trap.
The factory GT cars again provided us with some major drama in the opening corner with contact between a few cars leading to some retirements. The BMWs showed some strong pace during the weekend and while they didn’t set the outright fastest lap time, they did set the fastest average lap time. The long wheel base of the BMW M6 GTLM provided the car with some added stability through the fast corners of the Austin, Texas track. Despite setting the fastest race lap, the Ford GTs were both at the bottom of the list through the speed trap. Overall the entire GTLM class was within 1.8 seconds on average lap time and within 6 mph through the speed trap.
Only three Prototype Challenge cars started the race. The #38 car from Performance Tech was way ahead of the rest of the field by setting a fastest lap time that was nearly 2 seconds quicker than the next quickest car.
In the prototype class the weekend belonged to Wayne Taylor Racing and drivers Ricky Taylor and Ricky’s Brother. A stunning lap in qualifying saw them start on pole by just over 1.5 seconds. In the race they were 0.6 a second quicker on fastest lap time and 1.1 seconds quicker on average lap time than the next quickest car in class. Breaking it down a little but it appears that the WTR crew found something in the setup for COTA as the other two Cadillac DPi.V.R’s were over a second slower. That setup help that WTR found was through the corners specifically. The #10 car was 0.61 seconds quicker through Sectors 2, 3 and 4 and additional 0.64 seconds quicker through sectors 9, 10 and 11. All sectors that should favor a car with good handling. If the Cadillac struggled anywhere it was through the speed trap. The three Caddy DPi.V.R machines were in the 158-160 mph range while the turbo charged Nissan DPi and Oreca Gibson were in the 160-162 mph range. Speaking of speed traps, the Multimatic/Riley was very slow through the speed trap, 7 mph off the quickest car. That said, they weren’t that far off of the leaders overall pace as the car set quick times through the twisty bits. Overall the entire prototype field was within 2.3 seconds on average lap time (1.2 if you ignore the WTR car) and about 7 mph through the speed trap.
Drive time is a relatively simple rule that has cost some of the best teams wins or podiums the last few years. Adding up the sum of the lap times of all the drivers we can get a rough idea of the total drive time. These numbers are skewed a little bit due to teams that had mechanical issues that lead to extended driver stints, therefor the lap count column is the better indicator. One of the first things that stands out is Johannes van Overbeekes 66 total laps. Co-driver Ed Brown drove a short, 15 minute stint and JvO got right back in the car. Other drivers that did long stints were Alexander Sims, John Edwards and the rest of the pro drivers in the Pro-Am classes.