DAYTONA BEACH, Fla. – William Byron backed up his victory in the second Bluegreen Vacations Duel on Thursday night by posting the fastest speed in Friday evening’s Daytona 500 practice.

Byron’s No. 24 Hendrick Motorsports Chevrolet turned a best lap of 204.587 mph around the 2.5-mile Daytona International Speedway.

“We were being super aggressive in our first run, trying to see what we could do,” Byron said. “On our second run, we tried to catch up to the front pack to see what our car could do.

“I’m comfortable with what we have right now.”

Ryan Preece was second in his No. 37 JTG Daugherty Chevrolet at 204.095 mph. Chase Elliott’s No. 9 Chevrolet was third at 203.868 mph followed by Ty Dillon’s Germain Racing Chevrolet at 203.422 mph.

Tyler Reddick rounded out the top-five at 202.922 mph in his No. 8 Richard Childress Racing Chevrolet.

Typically, on a Friday practice session before the Daytona 500, many of the teams decide to preserve their cars by remaining in the garage. Mayhem at Daytona lurks around every corner.

Friday’s early-evening session was different. Ten minutes into the session, 31 of the 40 cars in the race were on the rack with three-wide racing going into turn two.

Thirty minutes into the session, the top-five cars on the track were the Joe Gibbs Racing Toyotas of Denny Hamlin, Erik Jones, Martin Truex Jr. and the No. 95 Leavine Family Racing Toyota of rookie Christopher Bell. Kyle Busch’s No. 18 Toyota rounded out the Toyota contingent.

In the draft, cars exceeded 200 miles per hour.

Cars on the track were testing handling in both single-file and multi-lane competition to determine how the cars will perform throughout Sunday’s 62nd Daytona 500. A few even tried bump drafting, a tactic that will likely be used in the race.

Another major change to Friday’s action was the weather. Thursday night’s qualifying races were held under hot and humid conditions with rain delaying the start of the first race. Friday’s temperatures were much cooler, in the low 60s with gray, overcast skies.

Sunday’s forecast for the Daytona 500 is partly cloudy with a high of 71 and a low of 62.

In the final 15 minutes, two lines of cars formed to test side-by-side and side drafting, with Hamlin still setting the pace before Bryon took over the top spot at 203.083 mph.

He would increase that speed by nearly 1.5 mph before the end of the session.