Go wide and let the lats run the show.
Think about driving your elbows down to your ribs. The wide grip puts the work on your lats.
Going well outside shoulder width strips the biceps of most of their leverage and hands the pull almost entirely to your lats. Driving the elbows down toward your ribs from that wide overhand position works the back through the line that builds width, and the reduced arm assistance is exactly why these feel harder than any other pull-up. They belong at the top of the bodyweight back hierarchy for anyone chasing a wider frame.
The wide grip cuts down how much your biceps can help, so the lats have to do nearly everything through a mechanically tougher line. Fewer reps here is normal, and it is also the point.
Comfortably outside shoulder width, wide enough that the elbows drive down and out rather than straight back. Going extreme just shortens the range and beats up the shoulders without extra benefit.
Use slow negatives, band assistance, or wide-grip lat pulldowns to build the pattern, and keep some closer-grip pull-up volume in the week. Strict partial-count sets beat kipping your way to fake numbers.
