Exhaust Manifolds

I'm looking for a set of OEM E.M. for my 304 swap. My JEEP is a 73 and the engine is a 74 304. I will be using an OEM intake and MC 2100 carb. Is there any specific year range that I need to be looking for? And it seems like that I read somewhere that one or both manifolds need to be from a CJ. Whats the deal with that?

 

Re: Exhuast Manifolds

The two main changes are 1) with or without air injection ports, and 2) driver's side drop in the Wagons and J-trucks starting in 1980.

With the change in drop in 1980, the driver's side manifold changes. But the Wagon, J-truck, Commando or CJ manifolds from 1979 or earlier will be fine. My parts book confirms this.

 

Re: Exhuast Manifolds

To go a little further...the driver side drop is to get around the clutch hardware...later EM's will have the drop to close to the firewall...the early ones don't.

 

Re: Exhuast Manifolds

I have an extra set. Pm sent

 

My 73 with a 304 has some sort round hole on top of the passanger header. What would this be? I will take a picture when I get home.
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Is the round hole actually in the casting, or is it in the sheetmetal piece riveted to the cast iron manifold? My 73 manifolds have a sheetmetal piece over the passenger manifold to duct warmed air (not exhaust air) into the original air cleaner horn. I don't use that anymore. I have a big honkin' K&N filter housed in some ginormous crinkle black Chrysler air cleaner assembly.

 

I guess it is probably a sheet metal piece like you say. I thought that's maybe what it was, but I wasn't totally sure. Thanks!

 

It seems like I'm running late '70's Waggy exhaust manifolds with out any problems