Hello-
I was wondering if the heads from a 1989 5.0 will fit onto my 71 302? And if so, will it make a difference? A friend of mine saw that I had them laying around and said it would probably let my engine "breath better." Does anyone know if there are any fitment issues, and if it is even worth it?

Thanks,

 

Fit? Yes. But you may lose some compression ratio. I don't recall what the combustion chamber sizes are for the heads, but it would be good to know beforehand.

Really, the only flow difference is in the exhaust port casting, which Ford updated in '87. With a die grinder and some patience, you could open up your existing exhaust ports to free up some airflow. IMO, this would be the better route because it wouldn't require altering your valvetrain (the late model heads use pedestal-mount rockers and may require different pushrods as well).