I had a soaring operation based out of las vegas nv. Cht's would getting pretty high towing three folks in a 2-32 to 3k ft on a 105 degree F day. But there is a simple solution that we used to both get down quick for the next tow and keep temps normalized.

After release we would throttle back to around 1400 rpms but then drop flaps and use a hard slip to decend. The hard slip would give us greater than 1500 fpm down while it also disrupts the airflow into the engine thus maintaining cylinder temps. This worked fantastically and in over 800 hours on a 260 pawnee towing one year we never had a single cylinder cracking issue.