[mr0077]

Your engine guy is wrong, you want that motor to run at or above 180F. The T-stat is the minimum temp it will run at, so if you put in a 160 T-stat and it wants to run cooler, it will hover around 160, but if it wants to run hotter, it will. Running it cold is hard on a street motor, and I doubt if your 533 will stay at 160 anyway.
On the fan, you shouldn't need it all the time, put in a fan temp switch set for 180 or higher