Traditional dumbbell pullovers only engage the lats for a small portion of the exercise. Do decline pullovers using a cable machine to keep tension on the lats for the whole lift.
Most bodybuilders use pullovers for the lats, but how much impact does it really have on those muscles? Looking at the force angle, we see a movement where the dumbbell is being pulled downward by gravity. As lifters go through the pullover motion, they're essentially traveling in a horizontal pattern while the dumbbell's force angle is still pointing straight down.
Since the lats become involved when the force angle simulates a vertical pull motion, it means the lats would only really be engaged for a small portion towards the beginning one-third of the movement, before other muscles enter the scene. You can get more bang for your buck by performing a different variation.
Decline pullovers with a cable keep the tension on the lats due to a force angle that opposes them for the entire duration of the lift. Use the bench and cable instead of the dumbbell if you're looking to really torch your lats.