Ford's Infamous E6TE


E6TE photos by Mark Harrell

In 1986, Ford began to install the E6TE cylinder heads on their 5 liter V8 engines. I have to ask myself, and I do this in a caring and nurturing way, but, what the Hell were they thinking?

As you can see, the intake valve is heavily shrouded, as if Ford was trying to redirect the flow out of the valve pocket. The deck (quench area) also divides the valves somewhat, I guess to promote swirl.

While many folks defend the merits of the E6TE, they also have to ask themselfs just one question: "Why do you think Ford replaced the E6TE after only one year of use"?
In 1987, the E7TE replaced the short-lived E6TE. The end view on the left is an E6TE. while the end view on the right is an E7TE. While the casting marks seem to be slightly different, you cannot rely on these differences when trying to identify an E6TE head.

About the only easy way known to modern science to identify an E6TE casting is to inspect the spark plug hole. Here, there is a decernable difference.
The photo on the left is a close-up of an E6TE spark plug hole. On the right is an E7TE spark plug hole.
Look closely and you can see that the E6TE spark plug hole has a deep recess from the casting surface to the plug threads, while the E7TE spark plug hole does not have the deep recess from casting surface to plug threads. This difference in the spark plug holes is the only 'practical' way I know of to identify an E6TE from the exterior.
The only other way to identify the castings, short of removing them, is to remove the intake manifold and slip a mirror under the casting to try to read the casting marks.

So, what do you do with an E6TE?
Some flow data I have seen shows that it does not flow as bad as it looks up to .5" lift. The flow numbers are similar to stock E7TEs. Also, with the high swirl chambers, the net power output may be slightly higher than the E7TE. But one thing most people will tell you is that they run out of steam at pretty low RPMs. So while they might be a good choice for high torque/low RPM applications, they don't appear to be the best choice for higher RPM applications. I would guess that the flow could be improved. In fact, there certainly appears to be enough material to form a custom chamber shape for certain applications.
Also, the E6TE valves, I believe, sit higher in the chamber. This means that bolted to a later block with pistons that have valve reliefs, a higher valve lift should be possible.

Let's review!
* 1986 Ford introduces the E6TE casting on their V8s
* 1987 Ford replaces the E6TE castings with the E7TE, which is used through 1993.
* The easiest way to identify the E6TE casting is by the spark plug hole.
* The E6TE has a high swirl chamber that seems to produce good low end torque, but limited RPMs.

A special thanks goes out to Mark Harrell for the most excellent E6TE photos. Thanks Mark!