That used to be the hot setup back in the early 80's back when 16" and 17" wheels were unheard of and the High Performance Mustangs mounted the ungodly expensive TRX tires.
I have P215/60-HR14 tires currently but I am aware of several people who used to run them. I was told you need to have good shocks, struts, and springs because if the body sags you might get alot of body rub.
And the Mustangs I have seen with P235/60-14's looked very nice, the tires fill the wheel well very nicely.