The Daytona Prototypes outpaced their LMP2 opposition in the new United SportsCar Championship's top class ahead of qualifying for the Daytona 24 Hours.
Briton Richard Westbrook headed the times in the Prototype division during both sessions of free practice for the opening USC round this weekend, ending up with a best of 1m39.279s aboard his Spirit of Daytona Coyote-Chevrolet Corvette DP.
That put him just under three tenths of a second up on Christian Fittipaldi in the similar Action Express Racing Coyote and 1.2s ahead of the fastest P2, the OAK Racing Morgan-Nissan LMP2 driven by Olivier Pla.
The difference in times came despite changes to the regulations under USC's Adjustment of Performance rules designed to slow the DPs, announced late last week.
Westbrook ended up six tenths shy of Fittipaldi's fastest Prototype lap at the official Daytona test earlier in the month, but the OAK car was seven tenths slower than the best P2 mark at the test.
Fastest in GT Le Mans over the course of the 90 minutes of free practice was the SRT Viper GTS-R driven by Jonathan Bomarito, whose time of 1m45.016s put him two tenths up on team-mate Marc Goossens.
Colin Braun ended up quickest in the one-make Prototype Challenge class for CORE Autosport, while Daniel Serra was listed as fastest in GTD at the wheel of his Scuderia Corse Ferrari 458 Italia GT3.