What was the outside air temp? At about 40, then 150 would be okay. Above that it could be a little low. I don't have an aluminum radiator or heads, but mine runs about 180 this time of the year (below 50 degrees), and about 190 to 200 in summer. Some say if the water temp is not over 170 you're not burning all of your fuel.

Every car is a little different.