Chambered head Question

[shadowgray396]

Just got a call on a 70 CTX motor that a friend know someone has. My question is it has open chambered heads, were they available in 70?. I have not had the chance to go see it in person yet so I don't know the date codes of the heads. I know the motor is a January motor and my car is a february built car. Are open chambered heads fine for just driving around. Everyone I have talked to seems to have the closed chambered heads. Not a motor guy so educate me. Thanks
Ray