Cadillac Racing’s Renger van der Zande posted the fastest lap time in the opening practice session for this weekend’s 12 Hours of Sebring, topping the IMSA GTP timesheets with a 1:48.279s lap time in the #01 V-Series.R.
It was a Cadillac 1-2 as last year’s 12 Hours of Sebring winners Action Express Racing posted the second-fastest time of the session with the #31 V-Series.R, courtesy of a 1:48.758 lap time set by Jack Aitken.
The fastest of the non-Cadillac entries was the #6 Porsche Penske 963 machine, at third-fastest with a time of 1:48.941 thanks to Nick Tandy.
Brendon Hartley (+0.796) and Louis Deletraz (+0.940) completed the top-five overall/GTP in the #10 and #40 Acura ARX-06 WTR-Andretti machines.
The first of three practice sessions on Thursday commenced at 10:05 local time (14:05 GMT) at the Sebring International Raceway in Florida and just two minutes in a red flag was flown with Gianmaria ‘Gimmi’ Bruni coming to a halt in the #5 Proton Porsche 963.
It was a brief stoppage as the car was cleared and after five minutes green flag running resumed, but the #5 Porsche was one of four cars not to set a time in the session, the others being the #1 Paul Miller Racing GTD Pro BMW M4 GT3, the Daytona 24 Hours-winning #18 Era Motorsport LMP2 Oreca and the #34 Conquest Racing GTD Ferrari 296 GT3.
The Iron Lynx squad had a tricky time getting up to speed with their Lamborghini SC63, making its IMSA debut in the GTP category this weekend and took half an hour to get a time on the board as the #63 machine wound up 10th overall, 2.683 adrift of top spot.
Meanwhile, 1.396 seconds covered the top-nine cars.
In LMP2, TDS Racing topped the standings with Mikkel Jensen setting a 1:51.342 lap time in the #11 Oreca 07.
The #22 United Autosports Oreca was narrowly beaten on the timesheets with Paul di Resta posting the second-fastest time in LMP2 just 0.021 shy of the TDS pacesetters.
Rounding out the top three in LMP2 went to the #2 United entry, 0.216 back from the #11 car thanks to Ben Hanley’s effort.
In GTD Pro, Jack Hawksworth topped proceedings in the #14 Vasser Sullivan Lexus RC F GT3, setting a time of 2:00.202.
Second in GTD Pro and second overall out of all of the GT runners was Daniel Serra in the #62 Risi Competizione Ferrari, 0.094 shy of Hawksworth.
Third out of the GT entries and first in GTD was the second Vasser Sullivan car, with Parker Thompson guiding his #12 Lexus around the bumps of Sebring in 2:00.606.
Next up was the third GTD Pro runner, Seb Priaulx in the ever-popular ‘Rexy’ AO Racing #77 Porsche 911 GT3 R, setting a time of 2:00.798.
The second and third-fastest GTDs took the sixth and eighth-place spots out of the GT contingent, led by Canadian Mikael Grenier in the #32 Korthoff Mercedes-AMG GT3 (2:00.951) and followed by Antonio Fuoco in the #47 Cetilar Racing Ferrari (2:01.086)
Second practice commences at 15:05 local time (19:05 GMT).