1980 CJ5 258 Air Intake / Exhaust Manfiold Configuration
I saw a post about them being married by configuration before 1981. I had a buddy that warned me about this in the beginning but wasnt certain since it was a 258... Since mine is an 80, I guess this applies to me. And wouldn't you know it, I get a call from the mechanic today saying my Air Intake wont bolt onto the exhaust manifold.
It is a omix-ada part number 17622.05. What's even more of a pisser, I have already paid to get the old intake cleaned up and ceramic coated (as well as the air intake). So the million dollar question is what Air Intake do I need to get that will be compatible with the new exhaust manifold? Or, what manifold do I need to get to work with the current air intake.
Any information would be greatly appreciated.[/QUOTE]
For the life of me I can't figure out what you're asking. Do you have a newer intake manifold - and you bought an older exhaust manifold that matches with the older intake?
If you have a newer intake, the one with a water jacket and heated manifold plate, the exhaust manifold you'll need is one like this: CJ exhaust manifold for 81-8? You'll also need to either plug the EGR port on the intake and exhaust manifolds, or buy the connector to mate them. It's an S-shaped tube and you can get it for about $35 at your Jeep dealer - tell him it's for a 4.2 YJ, they use the same part.
Or are you trying to find an intake manifold to match your new exhaust manifold? If that's the case, you can pretty much only find them used on eBay for usually less than $100: 4.2 Intake #1
More confused. The "old" intakes are cast iron and don't have a heated water jacket (i.e. the coolant ports). The "new" intakes are like those I posted on eBay, with a heated water jacket, made of aluminum.
The "old" exhaust manifolds are like the one you linked in your first post - they mate up perfectly with the "old" intakes through a port about 3"x3" square. The "new" exhaust manifolds are like the first link I posted, with a simple 1/2" port that you have to link to the "new" intakes with a curved pipe, available through your Jeep dealership.
If you have a picture of your intake, I can verify that it's the "new" style, but from the sounds of it - that's what you have and you'll need an exhaust manifold like this one: '81-86 4.2 exhaust manifold, as well as the curved pipe to fit it to the intake.
Is there a chance you have an aftermarket intake manifold - a Clifford or something? If that's the case, neither exhaust will mount with it very easily, and more likely than not you'll need an exhaust manifold from that particular manufacturer.
Maybe the air intake is not original? and was never hooked up to the old exhaust manifold? Or maybe the engine itself is not original? and is a 81 or later model? or maybe something aftermarket? All is possible with a 30 years old vehicle....
Is the problem they won't bolt together? but can still bolt to the engine? if thats the case then its probobly not a problem. Most of those pre-81 manifolds have a non-functional heater anyway.
I am not certain if its the original intake or not. But it definitely was hooked up to the old exhaust manifold. The engine was replaced 15 or so years ago with a crate engine of some type...I remember my brother in law telling me about it. Every piece of information I have on the Jeep is its a 1980 CJ5.
You're right, they wont bolt together but can still bolt to the engine...
Thanks for all of the help.
The intake you have shown is the same as the one on my 82 model. So somewhere in the life of your jeep it got swapped. It was married to the manifold tht you had, but someone has plugged the holes as I am in the process of doing to mine now. The steel pipe that married them was part of the EGR system and many people delete it when doing modifications if not in an emissions state. You may have to just use 2 seperate gaskets from felpro for your intake and exhaust or they may both seal with the single gasket. The gasket kit I got had both gaskets but I only used the one.
"It's not about how hard you can hit, it's about how hard you can get hit and keep moving forward!"
The problem with bolting them to the head is the mounting flange is different between the two types. Since both manifolds use the same bolt with a thick washer in several locations, the thickness of the mounting flange on each has to be the same or you'll never get one tight while the other will be tight.
Sorry to say, but at this point you need the newer (81 and up exhaust manifold) or the older type intake manifold that will work with the "new" exhaust manifold.
OK, guys...thanks for the help. I really appreciate it. I am ordering another exhaust manifold, 81 and up, so it can be compatible. I have to keep moving forward on this rebuild so I dont stall out....I have a brand new, ceramic coated exhaust manifold I will make somebody a heckuva deal on.