74" Cylinder growth verse Intake manifold gap

[jgbrown59]

I stopped worrying about it, Duke!

After I successfully reconditioned a few EL manifolds for FLs.

(I challenge anyone to show me an OEM '48-'49 manifold of anything but EL width; They are absent from the fossil record.)

How would you measure the distance between nipples at operating temperature?

....Cotten

Cotton -

Included are pics of a 48-49 3 3/8" wide intake manifold. I found this in Davenport around 2016-17. I assume its an original.
Since its installed to a newly refreshed motor (48FL), with peak seals, I can't prove its really 3 3/8" so you'll have to take my word for it (not taking it apart). I was shocked I found it (I knew what I was looking for) and that it was in such good condition.

The bike came with a 3 3/16" manifold, pic included, (which I still have). I assumed it was for a 61"motor based on research.


48Intake-2.jpg48Intake-1.jpg48Intake-3.jpg

[T. Cotten]

Wow Thanks, JG!

I assume the clean assembly is the wide one?

Wouldn't 3 3/16" be even narrower than EL?

Let us all note not only the fits of the silver-soldered assembly, but that the later ones were turned upon the spigots:
48-49MANIS.jpg

Your wide manifold is a true hen's tooth!
(and your rough one is noteably cruder than most...)

....Cotten
PS: Good luck with "peak".

PEEK works great, but it must be fastidiously fitted.

[jgbrown59]

Yes, the clean assembled manifold is the 3 3/8" version. As you can tell I had it CAD plated. To confirm, it is made of steel. According to the Palmer books, the 61" version is 3 1/4" wide so I agree this one is a bit shorter and it looks worse than it is.