Kentucky Speedway's 1.5-mile tri-oval served as proving ground for two top NASCAR Winston Cup teams and a research facility for two others during test sessions to be completed today.

Eel River Crew Chief Barry Dodson used the first day of his test session to reacquaint driver Mike Bliss with the No. 27 Duke's Mayonnaise Pontiac. Bliss recently replaced Kenny Wallace as the team's primary pilot. "We're just knockin' the rust off," Dodson said.

Bliss, who practiced the No. 2 AC Delco Chevrolet for Kevin Harvick before last month's NASCAR Busch Series "Outback Steakhouse 300" at Kentucky, said he was working on establishing baselines with his Eel River Crew.

"This is the first time I've driven the car this year," Bliss said. "We're just getting me back in the seat and trying to build notes. We'll go over shocks, springs and try to figure out what this (Goodyear) tire wants."

Hendrick Motorsports, home of current Winston Cup points leader Jeff Gordon, gave stand out Busch Series driver Jimmie Johnson a taste of Winston Cup racing by getting him seat time in the No. 24 Du Pont Chevrolet and the GMAC Racing research and development car. Johnson will move from the Herzog Motorsports Busch Series car to a Hendrick Winston Cup car next season.

"We're havin' fun," Johnson said. "This is my first time in a Winston Cup car and we're just finding our baselines. We're working on chassis, aero(dynamic) and motor stuff to find new secrets and confirm some stuff we already know. We want to make sure of what it's (the No. 24) is doing before they throw it at Jeff."

Johnson, who also drove in last month's "Outback Steakhouse 300" at Kentucky, said he noticed a significant difference in the way the Winston Cup and Busch cars drove on the track. "The track is a totally different animal for me. The Cup car has more horsepower and runs faster at the end of the strait. I can feel the Hendrick advantage. The track is relatively smooth (in the Cup car), some of the things that affected my Busch car weren't affecting the Cup car."

John Andretti was making his first visit to the state-of-the-art Kentucky facility with the Petty Enterprises team. "This is our first time here and we're trying to figure out what it's like as far as comparing it to another track," Andretti said. "It's unique, like a Vegas-banked Chicago." Andretti said the team was reviewing the team's entire racing system by establishing its baselines and testing "a variety of things."

Casey Atwood and Evernham were pursuing a similar track for the No. 19 Dodge.

Kentucky Speedway's next racing weekend is July 13-14 and will feature the NASCAR Craftsman Truck Series "Kroger 225" and ARCA RE/MAX Series "Bluegrass Quality Meats 200."