Reed held off a last-lap charge by Ken Roczen when a lapped rider got between them, earning his 43rd career victory and matching the Angel Stadium record with eight. The 31-year-old Aussie also won in Anaheim last month, snapping a 22-race winless streak with his first victory since 2012.
"It was a tough racetrack tonight," Reed said. "It was about making smart choices and putting yourself in a good position to ride 20 solid laps. This win means more to me than the last one (on Jan. 18) where I came from behind because it's tougher to go out there and lead all 20 laps. We had our bike dialed in tonight and it was one of those nights where it felt one with me."
Three-time defending series champion Ryan Villopoto finished third before a crowd of 42,139. Reed moved within two points of Villopoto in the 450SX season standings.
"The track was super tough," Villopoto said. "I got a great start but Chad was able to get by me. Ken was running similar lap times and was able to get by as well, but to end up on the podium is always a good thing."
Dean Wilson raced to his first win of the year in the Western Regional 250SX Class. It was the seventh victory of his career and first since last year's season-opening race of the Eastern Regional 250SX Class Championship in Arlington, Texas.
"This win really means a lot to me," Wilson said. "This is really emotional for me. I gained some good points and we still have some races left."