How are the roads in Turkey now? If they're anything like what the West Germans found in the East after unification, there will be quite a lot of repairs and modernization to be done before the roads resemble anything like a Western-style superhighway.
It really depends. Istanbul-Ankara has full on eight lane or larger highway for parts of the journey, but anywhere east of that....well.....
It generally follows development patterns. The coasts, the west, and anywhere leading to Ankara have decent road networks, but nothing like a US superhighway. Much more in line with general southern europe road development. That said, there is a large amount of road construction that has gone on in recent years.
The modern Turkish passenger bus system is really the best I've ever experienced. Beats the crap out of Greyhound, that's for sure. In-drive movies, all the tea you could drink, little snack cakes...aaah. If only the rest stops were more frequent.
But I digress.
The possibility of a surviving Menderes/Demokrat Partisi government is interesting in and of itself, and is pretty much essential to the highway system taking off. Turkey in the 50's/60's was a heavily statist economy; something the American-friendly DP wanted to move away from. Part of the Turkish development schemes- before the DP came along and after it was removed- was an attempt to cultivate local industry through Import Substitution Industrialization, which called for pretty epic protectionism. Part of this was something like a one hundred percent import duty on cars, which I think may have persisted to this day.
While Turkey now has a car industry focused on building cars for the European market (several European car conglomerates maintain factories in Turkey, labor prices, etc. etc.) or for domestic/middle eastern consumption (like every third cab in Cairo was a TOFAS Sahin), this was NOT the case in the 1950's.
Basically you would have Menderes rolling the dice on a massive highway system in a country where there really was no mass personalized motor transport. To do that he would need to 1) change tariff laws AND 2) get enough cars on the road to justify expanding the road network, which IMO, needs way more political capital than he had.