New cars in TUDOR championship

Porsche's only model eligible for the GTD category is the new GT America, which will make its competition debut at the Rolex 24.

Nine cars were at the Daytona test, with up to a dozen expected for January's event.

The GT America is a modified version of the Porsche 911 GT3 Cup, featuring different front and rear bodywork and paddle-shifters.

"I like everything about it," said Madison Snow, driver of the No. 58 Snow Racing/Wright Motorsports/JDX entry. "It's a lot cleaner and smoother, and the paddle shifting is super. The dashboard is different, but you get a lot more information out of it. It's a great car."

BMW Z4 - After years of running a BMW M3 in Rolex Series GT competition, Turner Motorsport is testing the BMW Z4 it will race in the GTD class in 2014.

The team obtained the new car four weeks ago, and shook it down successfully recently at Road Atlanta.

Paul Dalla Lana, Dane Cameron and Pedro Lamy tested the car at Daytona.

"We're going to look at the data and see what it says," team owner Will Turner said.

"The consensus is this car is a little easier to drive than the M3, but we're still coming to grips with the balance."

SRT Viper GT3R - In addition to preparing the two SRT Motorsports Viper GTS-Rs in GTLM competition, Riley Motorsports is also fielding a Viper GT3-R for GTD competition.

"The GTD Viper is very different from the one I'm used to racing," said SRT factory driver Marc Goossens, who helped in early development of the new car. "You can't really compare one with the other. But Riley Technologies has so much experience that they know what they're looking for and this car has been very good right out of the box."

Ford EcoBoost/Riley - The new Ford EcoBoost/Riley made a splash at Daytona International Speedway in October before its first official IMSA outing.

Colin Braun drove a turbocharged DP prepared by Michael Shank Racing to a lap of 222.971 mph – the fastest lap ever recorded on the famed 2.5-mile oval.

Michael Shank Racing is the first DP team to utilize the new powerplant, installing Ford's new 3.5-liter, twin-turbo V6 EcoBoost engine in the No. 60 Riley driven by Ozz Negri and John Pew.

"The new turbo changes everything," Negri said. "We have to learn about the lag on the turbo and how it comes on, but it's been a lot better than expected."

IMSA