I run a 4 row (non-aluminum) desert cooler from Ames, with heavy duty clutch fan and all the proper fillers and still push 210 on hot days in traffic (with 4 sp). I'm not a fan of low thermostats. Whether you have a 160 or 190, they are both going to be wide open at 200F anyway. And the motor will run too cold on cool days. You have a 2 row rad? Was your car a 6 cyl?