Abstract: A gas turbine engine high pressure rotor with first and second high pressure turbine stages include first and second stage disks having first and second stage disk bores and a single tie rod therethrough. First and second bore annular flowpaths are radially located between first and second stage disk bores and tie rod. A means for increased cooling and/or heating in second stage disk bore is axially located within second stage disk bore. The means may include an airflow accelerator such as one or more annular ribs on the tie rod. A bore annular cross-sectional flow area between the second stage disk hub and the ribs may be substantially smaller than between the second stage disk hub and the tie rod. An axially unobstructed inlet into the second bore annular flowpath allows fully axially flowing and axially unobstructed flowing of second stage bore cooling air into inlet.