1970 Duster power steering issue

The original owner of my 1970 340 car put power steering on the car. He said it is too fast and will swap lanes too fast. He did not change the crank pulley. The pulley appears to be the same as the others as far as size. The car also has dealer installed ac in 1970 and those pulleys are the same. Does the pulley need changed? A smaller pulley to me would increase pump pressure.