There are small differences between the heads from the EA-EF. The EF onward has a chamber set up for better high rev performance/flow. The Valves are all the same, however, there are some port differences in the heads. For best performance, the head needs to be matched to your compression ratio, and the type of manifold you have.
The part number you describe is only useful to engineers.
91 represents the year the block was cast. The AA, AB etc is only a reference and Ford apparently do not use this as a reference at all
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Related Threads
?
?
?
?
?
Ford Forums
1.4M posts
115.4K members
Since 1999
Ford Forum is a community to discuss all things Ford. Check out our discussions on the Ford Escape, Mustang, Edge, F-150, Raptor, Explorer, Focus, Fusion, Fiesta and more!