All four manufacturers were given a wide swath of permission to create a new car for the junior series, and Ford responded with a racing version of the Mustang and Dodge responded with the Challenger.
Chevrolet and Toyota stuck with their Impala and Camry models, respectively, during an open test session Tuesday at Daytona International Speedway.
The new car, which is constructed identically with the Car of Tomorrow currently used in the Sprint Cup Series, will make its debut July 2 at the Subway Jalapeno 250 at Daytona. The new car is wider and taller to promote better safety.
The new car will make four other selected starts this season before becoming the full-time race car in 2011.
Instead of relying on the Fusion, Ford went with one of its most iconic brands, the Mustang. Dodge will campaign the Charger in the Sprint Cup Series and the Challenger in Nationwide. The two new entries in NASCAR are distinctive, especially since NASCAR allowed greater latitude to make them look like a passenger car.
The Dodge front grille is offset like the passenger car. The Mustang also has the look of a car you'd see on the street.
Chevrolet was prompted to build a Camaro, but the car company decided to stay with the Impala. There are some subtle differences between the Sprint Cup and Nationwide cars for Chevrolet and Toyota, but nothing like the sweeping changes by Ford and Dodge.
"Since I took over as (Nationwide) Director six years ago, the cars were very similar, the setups were very similar and we started on a path when we looked at developing this car to make sure we had enough differences to give ourselves our own identity," NASCAR's Joe Balash said.
Kevin Harvick's Impala was the fastest car during the single-car session at 181.598 mph, while Kyle Busch's Toyota was quickest in the drafting session at 185.395 mph.
"NASCAR learned some things that may or may not have been wrong on the (Sprint Cup) COT and they made some changes to this thing to see what we could do, see if the appeal comes back and the racing is better and we'll see those changes happen next door (in the Sprint Cup garage)," Busch said. "They do look a lot better."
Reach Don Coble at firstname.lastname@example.org.