It's not the tie rod ends, it's the steering arms. People either replace the steering arms with shorter ones(power-steering arms) or shorten the existing steering arms. When you turn, the tie rod ends travel in an arc, with the centre being the ball joint in the lower control arm, and the radius being the length of the steering arm. If you shorten the steering arm, you reduce the radius, but the length of the arc remains constant(as the steering rack still pushes/pulls the tie rods the same distance), therefore the angle at the centre of the arc must increase, which is your steering angle.
eg.
if the radius [r] = 200mm (steering arm)
and the arc length = 400mm (distance the tie rod end is pushed by the steering rack)
and the angle at the centre = θ (in radians)(the angle at the LCA ball joint between the steering arm in it's 'full lock to the left' position and 'full lock to the right' position)
s = θr is the equation for the arc length.
400 = θ x 200
θ = 400 / 200
θ = 2 radians (which is like 120 degrees of steering from lock to lock)
if you reduce the steering arm [r] to say 100mm
s = θr
400 = θ x 100
θ = 400 / 100
θ = 4 radians (which is like 220 degrees of steering from lock to lock lol)
The values are a bit extreme, but you can see how you would get more steering lock by reducing the steering arm length
If your original lock to lock steering angle was 2 radians (120 degrees) and your new lock to lock angle with the 100mm steering arms is 4 radians (220 degrees), to achieve the original lock to lock angle with the new 100mm steering arms;
s = 2 radians x 100mm
s = 200mm
Therefore the rack only has to move 200mm with the new steering arms to achieve the original amount of steering angle, as opposed to 400mm with the original steering arms, which means you turn the wheel half the amount of turns as you originally did, which = awesome