Lawrence was 21 of 28 for 214 yards. Brian Riley had five catches for 77 yards and two scores.
Valparaiso led early on Jacob Newman's 38-yard field goal, but that's as good as it got for the Crusaders.
San Diego (2-1) got an 18-yard touchdown pass from Lawrence to Riley with 3:40 left in the first half, then after a quick three-and-out, added Jack Flatau's 28-yard field goal just before intermission.
Lawrence hooked up with Joseph Jakubowsky from 29 yards out early in the third, and then connected with Riley again - this time from 24 yards - to make it 24-3. Daniel Cooney had a 9-yard touchdown catch to complete the rout.
It could have been worse for Valparaiso (0-3), but Kellan Hughes had two interceptions to thwart early San Diego drives.