Saturday’s TUDOR United SportsCar Championship test at Sebring International Raceway marked the first on-track appearance of IMSA’s new proposed updates to the Daytona Prototype, which showed encouraging pace despite limited running time.
Featuring a new diffuser, tunnels, dual element rear wing, carbon fiber brakes and larger, 5.5-liter Chevy V8 powerplant, Joao Barbosa took the No. 5 Action Express Racing Corvette DP to a best lap of 1:53.266.
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The time was just a tick over two seconds slower than Ryan Briscoe’s P2 pole-winning lap for this year’s Twelve Hours of Sebring.
“The first few laps I was really impressed how good the car was from the beginning,” Barbosa told Sportscar365. “I was expecting a lot more things [that had to be] fixed or dealt with but the car was good from the get-go. Obviously the setup was not perfect and was touching a little bit on the bumps.
“But other than that, the car has been running great. The brakes, the diffuser, aero, everything was better than I was expecting. I was really pleasantly surprised with the changes.”
Barbosa completed roughly 30 laps on Saturday, with co-drivers Christian Fittipaldi and Sebastien Bourdais not getting any seat time due to rain, which arrived by the late morning, and the team electing not to run any laps in the wet.
A limited number of cars turned laps in the rain-soaked afternoon session, which left AXR with limited data for comparison, particularly as both P2 cars here have yet to complete any dry running time.
According to team manager Gary Nelson, the DPs in their previous configuration had roughly a 6 percent performance deficit to the P2s, with two-thirds of that having already been made up with the new aero and mechanical updates.
“Typically, I’d like to come away knowing we’d need 2 percent with a roadmap that said, ‘This is where we’re going to find it,'” Nelson said. “We’re now kind of scratching our heads of where we’re going to find 2 percent, which turns out to be about 2 seconds.
“When a driver says everything’s good, you should be running faster than two seconds a lap off. We’re going to keep digging. We made some more changes and then the rain came.”
Barbosa added: “We know this car pretty well and know we can probably go a little bit faster. But at this point we still have 2 seconds to find. Saying that, I don’t know if this will be enough for the P2s or not, but it was very encouraging.
“The car had good grip but being my first time here with this car and never running the old car with the old configuration, I could not really compare much. Next week in Daytona is going to be a much better direct comparison.”
Nelson said the team spent the past two weeks modifying its Coyote-chassied DP, which included re-routing the exhaust from the rear to the sides, among the aforementioned other aero and mechanical developments.
Marsh Racing, with the support of technical partner Spirit of Daytona Racing, is also at Sebring with an updated DP but did not turn any laps on Saturday.
Both AXR and Marsh are expected to be joined by Michael Shank Racing and the Troy Flis-led SDR squad at Daytona next week, both of which will also be running in the proposed 2014 configuration.