1. Preheat oven to 350°. Stir together 2 1/2 cups cinnamon graham cracker crumbs and next 2 ingredients; firmly press mixture on bottom and up sides of a lightly greased 9-inch pie plate. Bake 10 to 12 minutes or until lightly browned. Cool completely on a wire rack (about 30 minutes).
2. Stir together semisweet chocolate, pecan pieces, and remaining 1/2 cup cinnamon graham cracker crumbs. Reserve 1/2 cup chocolate-pecan mixture to top pie.
3. Spread chocolate ice cream in bottom of prepared crust; top with remaining chocolate-pecan mixture. Freeze 30 minutes. Spread coffee ice cream over chocolate mixture. Cover and freeze 8 hours.
4. Beat whipping cream and coffee liqueur at medium speed with an electric mixer until stiff peaks form. Spread whipped cream mixture over pie; sprinkle with reserved 1/2 cup chocolate-pecan mixture. Cover and freeze 1 hour or until whipped cream is firm. Let stand 10 to 15 minutes before serving.