Engine Yet another 4.0 head swap question

[eazio]

I am currently swapping a 4.0 L 0630 head onto the AMC 258 i6 / 4.2l L block of a AMC 258 i6 / 4.2l (‘81 CJ7 ) and after installing the exhaust manifold on the new head it became apparent something was wrong. As shown in the pictures attatched, the exhaust manifold rests on the block.
A. is this okay? (doubt it)
B. Is this a matter of pipe bending? (doubt it)
C. Bought the cheapest exhaust manifold, is this a matter of buying something of better quality?

Has anyone else run into this problem?

 

[85yellowcj7]

This is how mine looks. Yes, getting the exhaust together is a little bit of a problem. Cobbled mine together with a few odd pieces. Almost has to go straight down the back. You have to get it away from, or leave room for the clutch slave

 

[85yellowcj7]

I have a Hydraulic clutch, you may not and so have a little different routing. Do you know how to modify the intake?

 

[85yellowcj7]

Here's a side pic of the manifold I used

 

[NP435]

In case you might be interested the Clifford hi Flow intake will fit that head, had it on a 4.0 that was carbureted conversion IDK if it will work with injection. Should you have interest pm me.

 

[eazio]

I have a Hydraulic clutch, you may not and so have a little different routing. Do you know how to modify the intake?

I don’t have a hydraulic clutch. i read extensively about the 4.0 head swap and I’ve never seen anyone mention this problem with the end of the 4.0 manifold hitting the block. I’ve run across a few posts that mention denting a few exhaust manifolds tubes to get the intake manifold to mate, but not this big of a mismatch…. I’m wondering if the manifold i bought ($90 Amazon special) is the wrong one or mismanufactured. The pics are really helpful. Thanks. I’m wondering if full headers will be a solution, or a different branded manifold will solve the problem. I don’t have welding capability, so cutting and reeled ig is not a great option for me. Any thoughts?

 

[JeauxBogan]

In case you might be interested the Clifford hi Flow intake will fit that head, had it on a 4.0 that was carbureted conversion IDK if it will work with injection. Should you have interest pm me.

Hey, thankfully this thread is open -- my AMC 258 i6 / 4.2l is out of the Jeep and I'm going to do the swap. I keep getting hub-bub from this "Jeep" shop near my house -- after being talked down to several times~ I'm not going back. But -- but.
I do need to solicit opinions for decision making. Your Clifford entry sparked my reply -- was thinking on reusing and doing the mods on the existing intake mated to the new head, topped with a Holly Sniper -- but I'm curious if the Clifford high flow double BBL for a 4.0 head on my setup is an improvement over stock...
The "Jeep" guy with over "thirty years of jeep Ownership.." hubub promises better results with a Hesco FPI>
Not to bogart into the original posters thread -- but its a related discussion and I'm curious to see the inputs b/c I'd eyed the same Amazon header.
Finally -- I did stumble across a thread that had MPG data from a Sniper -- good stuff.
Back to ya'll.
CL

 

[NP435]

Hey, thankfully this thread is open -- my 258 is out of the Jeep and I'm going to do the swap. I keep getting hub-bub from this "Jeep" shop near my house -- after being talked down to several times~ I'm not going back. But -- but.
I do need to solicit opinions for decision making. Your Clifford entry sparked my reply -- was thinking on reusing and doing the mods on the existing intake mated to the new head, topped with a Holly Sniper -- but I'm curious if the Clifford high flow double BBL for a 4.0 head on my setup is an improvement over stock...
The "Jeep" guy with over "thirty years of jeep Ownership.." hubub promises better results with a Hesco FPI>
Not to bogart into the original posters thread -- but its a related discussion and I'm curious to see the inputs b/c I'd eyed the same Amazon header.
Finally -- I did stumble across a thread that had MPG data from a Sniper -- good stuff.
Back to ya'll.
CL

The Clifford needs 400cfmm flow for optimum performance, I elected to save a couple hundred bucks and go back to the stock intake with my 2150 carb. It did work with the Clifford but the lack of flow and hard starting issues when cold, combined with vapor lock/vacuum stuff at altitude on hot days sent me to the stock intake, cheaper than a new 4bbl 500cfm Edelbrock any way. My Clifford is the 47-500. My CJ runs way better now than before.

 

[JeauxBogan]

The Clifford needs 400cfmm flow for optimum performance, I elected to save a couple hundred bucks and go back to the stock intake with my 2150 carb. It did work with the Clifford but the lack of flow and hard starting issues when cold, combined with vapor lock/vacuum stuff at altitude on hot days sent me to the stock intake, cheaper than a new 4bbl 500cfm Edelbrock any way. My Clifford is the 47-500. My CJ runs way better now than before.

I've been trying to find the approximate cfm (as applicable) to the 2bbl Sniper -- saw that the recommended Holly on Clifford was 390 ish. My Jeep was a Cali Jeep so the environmental octopus is now gone the way of the dodo and should breathe better no matter what. Not to tempt the unknown, I should probably stick with the stock intake as well -- will prob go with the full-on Holly kit from spark to the in-tank fuel system.

 

[JeauxBogan]

Eager to hear about the problem with that $90.00 Amazon header -- am thinking the same, that it is a manufacturing issue?