Earlier this month the Cadi’s were back on the track to kick off the second half of the season with Round 4 of the Cadillac Challenge Series presented by D3 and Toyo Tires. Round 4 went down on May 12th, Infineon Raceway, near Sonoma, California. Infineon’s 2.52 mile road course with total of 160 feet of elevation change was a great place to put these torque-monsters to work on a beautiful late spring day.

In class C1, the points leader Steve Collins and his flat-black 2nd Gen CTS-V and Ed Wagner in his white V coupe picked up right where they left off at during Round 1 at Fontana. There was also a new face near the top of the C1 class, as Sam Lollar joined in the fun in his Silver CTS-V. Lollar laid down his fastest lap of the weekend with a 2:08.95, but in the end it was Collins who won C1 for the 4th straight time with a best lap of 1:58.834.

For Class C2, there were lots of familiar faces at the top. WPA Racing’s Rich C. with his 2009 CTS-V, Karim T. in the Team Special K CTS-V. Running on sticky Toyo R888’s, Team Special K ran a 2:03.611 in the early session, while WPA Racing struggled to shave off every tenth they could to keep pace. After working hard to get things sorted, Karim finally pushed the Team Special K CTS-V to a fastest time of 2:01.134. Unfortunately it wouldn’t prove to be quite enough to take the win in C2, as WPA posted a blazing time of 1:59.336 in the final session of the day using a no-excuses, get-out-of-the-way, late-braking strategy. Even with a second place at Infineon, Team Special K still leads the C2 Class in points at the midway point of the season.

For the C3 Unlimited Modified Class, it was once again a battle between the D3’s Legionnaire and Team HeaVyweight Racing’s CTS-V at Infineon. With Bob Michaels behind the wheel of the Team HeaVyweight CTS-V, the bar was set high with a sizzling time of 1:56.848 in the opening session. Throughout the day, D3 fought hard to make a comeback, but in the end they were only able to post a best time of 1:59.314, meaning that Team HeaVyweight was able to further extend their points lead in class C3.

There may be clear points leaders in each class at this juncture, but there are still five more races left to go in the 2012 Cadillac Challenge Series, and anything can happen. This coming weekend, Willow Springs International Raceway in Rosamond, California will host Round 5 of the Cadillac Challenge Series on Saturday, June 2nd. Check out the gallery from Round 4 below, and keep it tuned to lsxmag.com for more updates on the series.