Running cold.Correct thermostat fan switch combination?

[ozkiwi]

I have a new 330hp crate motor and a champion 2 row 1inch tube radiator with twin 14 inch thermo fans mounted in a shroud.For some reason the guy who installed the motor paired a 160 thermostat with a 160 turn on fan switch and the motor never runs past 140 in normal driving and fans kick in city driving so it never goes past 150 on the dial.
I have ordered a 180 thermostat with a fan switch that kicks on at 200 and off at 185 is that the correct combination?
The mechanic who installed the motor said SBC like to run cool but I cannot find any support for that theory anywhere on the internet.