I'd like to run colder temperature thermostats in my 2007 Dodge Caliber R/T race car.

This is a dedicated race car. I will be racing it at Buttonwillow raceway in a few weeks and expect track surface temperatures in excess of 150F.

I know that the primary thermostat (head) fully opens at 193F and the secondary thermostat (block) fully opens at 226F.

Are there any lower temperature thermostats available?

Can I put a primary thermostat in the position for the secondary, so that I have the lower temperature thermostats in both positions?

 

To answer part of my own question, the block thermostat is an odd shape, and so there is unlikely to be an aftermarket lower temp version available.

I've emailed a few of the companies just to be sure, but I'm not hopeful...

 

I've verified that the thermostat for the head can use this Mishimoto unit:
But the block thermostat is an odd size, so I'm doubtful if there are any aftermarket units.