1968 Mercury Cougar GT-E 427/390 HP

[Rory McNeil]

Originally Posted by rawhide

Rory,
The 427 engines used an exhaust manifold that looked like the 390 engine. The 428CJ manifolds were far better.
regards, Roland

You are right Roland, they used the 390 GT style exh. manifolds. Funny thing is, in that Cougar ad/brochure that Hemi Moose posted, the drawing of the engine shows it wearing the exhaust manifold for a 66-67 Fairlane, which is not correct for the Cougar 427.

[rawhide]

Originally Posted by Rory McNeil

You are right Roland, they used the 390 GT style exh. manifolds. Funny thing is, in that Cougar ad/brochure that Hemi Moose posted, the drawing of the engine shows it wearing the exhaust manifold for a 66-67 Fairlane, which is not correct for the Cougar 427.

Rory,
I knew that the manifold in the picture was not correct but did not know what it fit. I had a set of those heads for years and sold them about seven years ago to a local who was restoring his GTE. I compared them to a pair of CJ heads and other than a difference in the exhaust bolt pattern I could not see any difference. During machining of the head it appeared that they had machined the CJ exhaust pattern in them and then filled the holes that were not correct and redrilled them. If my memory does not fail me it was four or six holes per head.
Roland

[Hemi Moose]

[Rory McNeil]

Originally Posted by rawhide

Rory,
I knew that the manifold in the picture was not correct but did not know what it fit. I also had a set of those heads for years and sold them about seven years ago to a local who was restoring his GTE. I compared them to a pair of CJ heads and other than a difference in the exhaust bolt pattern I could not see any difference. During machining of the head it appeared that they had machined the CJ exhaust pattern in them and then filled the holes that were not correct and redrilled them. If my memory does not fail me it was four or six holes per head.
Roland

The GTE 427 used the same head castings as the early 68 428CJ heads, I also had a pair (casting # C8AE-J). You are right, while the CJ head (C8OE-N) has a 16 bolt exhaust bolt pattern, using 4 bolt holes per exh. port, the C8AE-J head has the 14 bolt pattern, similar to the 390 GT cars, 4 bolt on either end, with the 2 center exh. ports "missing"the lower vertical bolt hole. Also, where the upper vertical bolt holes on both the CJ head, and all the 2 bolt truck and big car are all at the same height, the 14 bolt "GT" pattern heads have the upper vertical bolt holes located lower by about 3/8" for the end cylinders. Between that, and the 2 different exh.port heights used depending on the head, its very easy to have exhaust leaks if the headers used don`t have the correct flanges. In addition, most of Mr. Gaskets header gasket applications are incorrect, and have been for many years.