97 4.6 engine with 5.4 head

[Rydman313]

Just curious if anyone has ever heard of using a 5.4 cylinder head on a 4.6 engine. I'm replacing a crankshaft in one currently, and during disassembly I noticed that the head on the left-hand side has 5.4 cast in it where the right-hand head says 4.6. I'm told that the 5.4 head isn't supposed to interchange with the 4.6 head, but aside from having an outrageous rod knock, the engine ran fine when I pulled it into the shop. Visually, the 5.4 head appears similar to the 4.6, i.e. valve size, camshaft & valve train orientation, etc. Any opinions would be greatly appreciated.....

[~manuel~]

Originally Posted by Rydman313

Just curious if anyone has ever heard of using a 5.4 cylinder head on a 4.6 engine. I'm replacing a crankshaft in one currently, and during disassembly I noticed that the head on the left-hand side has 5.4 cast in it where the right-hand head says 4.6. I'm told that the 5.4 head isn't supposed to interchange with the 4.6 head, but aside from having an outrageous rod knock, the engine ran fine when I pulled it into the shop. Visually, the 5.4 head appears similar to the 4.6, i.e. valve size, camshaft & valve train orientation, etc. Any opinions would be greatly appreciated.....

i had a brand new set of heads off of a blown 4.6 liter, which was replaced with a new one under warranty, this engine only had about 6,000 miles. they sat for over a year. my aunts expedition equipped with a 5.4 overheated and warped both heads and cracked one. well i figured what the hell, they were both non pi heads so i installed the 4.6 heads on the 5.4 block. the valve covers from the 4.6 were needed on these heads and that was all.this was well over a year ago has been running good ever since.everything looks the same on both 4.6 and 5.4 liter heads, although this is the only instance i have ever interchanged them.i think the only difference is between pi and non pi heads.

[Rydman313]

Thanks for your response, Manuel. I just finished installing the engine, and it runs like a top. I wonder why Ford told me the heads weren't interchangeable. Oh well, that's the way it goes, I guess.

[badasstour]

thats so they could get money for the heads, its all about the allmity dollar

[Rydman313]

You may be right about that.......