Dixon lapped Daytona International Speedway’s 3.56-mile road course in 1m36.012s in the Cadillac V-Series.R from Chip Ganassi Racing’s stable, in warm track conditions for this 90-minute session.
Dries Vanthoor set the early pace in the #24 RLL-run BMW M Hybrid V8, lapping in 1m36.828s before Louis Deletraz beat him by 0.163 seconds in the #40 Wayne Taylor Racing Acura ARX-06.
Kevin Estre’s factory-entered, Penske-run #6 Porsche 963 then went P1 with 1m36.396s, before Rene Rast beat that by 0.027s in the sister #25 BMW with 1m36.369s.
That mark lasted until the half distance point, when Sebastien Bourdais unleashed in the Ganassi-run Cadillac a 1m36.255s to beat Estre by 0.026s.
Bourdais' team-mate Dixon jumped in for the final moments of the session, setting fastest sector times in both the first and second sections of the track. He increased the #01 car’s advantage with a 1m36.012s, which underlines Cadillac’s credentials as a pre-race favourite.
Connor De Phillippi responded in the #25 BMW with 1m36.139s, getting within 0.127s of Dixon.
Behind De Phillippi, Estre and Vanthoor were Dane Cameron (#7 Penske Porsche), Jack Aitken (#31 Action Express Cadillac) and Deletraz.
The #85 JDC-Miller Porsche 963 was plagued by a driver’s door that kept coming open, with Richard Westbrook setting the eighth-quickest time ahead of Neel Jani’s Proton Porsche.
“I think it was my shoulder, we made a little tweak to the insert and I think it was pushing the door open under braking,” he told IMSA Radio. “Good to find this out now!”
The #10 WTRA Acura spent most of the session on high stands in the garage being worked on after a very brief run. It appeared again at the end of the session in Felipe Albuquerque’s hands but ended slowest of the GTP runners.
Toby Sowery held the top spot in his #04 Crowdstrike by APR ORECA at 1m39.407s in the early moments of the session, a time that remained fastest throughout the 90 minutes.
Ben Hanley was second fastest, by just over a tenth, in the #2 United Autosports variant, ahead of Charles Milesi (TDS) and Ryan Dalziel (Era Motorsport).
Katherine Legge was quick of the blocks in the GTD class, lapping her Gradient Racing Acura NSX in 1m46.585s, a couple of tenths clear of Jack Hawksworth in the GTD Pro class leading Lexus RC F.
Robby Foley was third quickest in the #96 Turner Motorsport BMW M4, ahead of Marvin Kirchhofer’s Pfaff Motorsports McLaren 720S and the Ferrari 296s of Albert Costa (Conquest Racing) and James Calado (Risi Competizione).
