It is possible to do 176.4 or 192 with the Pace-Car, but not with the M-Audio device.
What is needed is a device that supports word-clock and up to 24/192 like the Lynx AES16 card. This is Mode 1.
OR:
ANY device that uses asynchronous flow-control (such as the Tascam US-144) that also supports 24/192. Slave clock inputs can be added to these in order to work with the PAce-Car. This is Mode 2.
Unfortunately, it will not work in Mode 3 (tuned) at the higher sample rates. The Superclock4 is limited to 24/96 for tuning.
Steve N.