Plunge 2 lobsters headfirst into a large pot of salted boiling water and cook, partially covered, over medium-high heat 8 minutes (for 1 1/4-lb lobsters) to 9 minutes (for 1 1/2-lb lobsters) from time they enter water. Transfer with tongs to an ice bath and let stand until completely cooled. Return water to a boil and cook and cool remaining 2 lobsters. Remove meat from claws, joints, and tails. Save carcasses, shells, and any roe for another use (see "To Make
Lobster Stock" and "To Make
Lobster Oil"). Coarsely chop meat.