4.0L swap intake option - Rugged Ridge TJ “cold air” intake

bigwalton

Picture cravin' AK Postal nut
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#1
I have never had a good intake setup on the Postal since the 4.0l swap. I just got the Rugged Ridge TJ “cold air” kit and I’m happy with how this looks to be turning out after some modification.

I cut 3.5” out of the tube and will use a coupler to reattach (taped together here) anything XJ/TJ is too wide for me as is.
CAE9E6B8-19FF-4848-AAC4-CBB8E7D9A0F6.jpeg

View from on top. This mount would go to the TJ fender, I’m going to pick it up with a piece of 5/16” all thread with some locknuts to come up and then bend/clamp the all thread to the grille support.
A4B32A54-2D03-42FC-93A8-333EDFB19636.jpeg

I have a vent/filter on the front valve cover opening so I don’t run the PCV hose and my IAT is in the intake, so I cut this section out of the tube. You could leave both/either of you needed, there’s plenty to cut out. It’s nice that the tube comes up high over the valve cover to make room for anything you have running over the top of the engine.
79B328B0-A6CF-45D1-948E-4C318A01A419.jpeg

This is the kit. Would prefer black, but this will improve things 100 percent. I may swap in a shorter filter eventually to get it away from any spray off the serpentine belt in deep water.
319F22BD-21A0-443F-B4F4-E275072DB0F5.jpeg
 

Belizeit

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River Ridge
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La
#2
BW any reason you are not trying to gather your air from the outside (cold) instead of under the hood (hot) ?
 

mysunnshine

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Phoenix
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AZ
#5
I was thinking more like the front of the vehicle, filter location is good.
I agree. At about 150 degree intake air temp, the ECU takes out a flat 5 degrees of timing. Put a cold air intake on they said....You will gain LOTS of horsepower...SMH
 

bigwalton

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#6
I’m confused, where do you want me to put the filter in a swapped-in 4.0l CJ engine bay that’s better than this or that doesn’t require a snorkel?

I wanted it on this side to get away from the exhaust header on the other side at least.
 

bigwalton

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#7
If you’re talking about the “shorter” comment, I only meant the length of the actual filter itself, not the tube.

:confused:
 

bigwalton

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#9
I have no chance of welding together something custom to snake a filter out of the engine bay like you Errick, if that’s what you’re trying to say here. I also have no room for a stock TJ/XJ airbox. Therefore, short of a snorkel, what would you have me do that doesn’t involve buying a number of kits that I might be able to piece together to rig up something else?

I didn’t claim that this was any kind of cold air intake, that’s just what the kit is called. Any filter I can manage is going to sit on top of the engine, that’s all I can do. This is at least as far forward and on the opposite side of the engine from the exhaust header.
 

bigwalton

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#10
I put “cold air” in quotes for you in the title, happy now?

Note that I had it in quotes in the first post already.
 
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mysunnshine

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Phoenix
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AZ
#11
I have no chance of welding together something custom to snake a filter out of the engine bay like you Errick, if that’s what you’re trying to say here. I also have no room for a stock TJ/XJ airbox. Therefore, short of a snorkel, what would you have me do that doesn’t involve buying a number of kits that I might be able to piece together to rig up something else?

I didn’t claim that this was any kind of cold air intake, that’s just what the kit is called. Any filter I can manage is going to sit on top of the engine, that’s all I can do. This is at least as far forward and on the opposite side of the engine from the exhaust header.
If you wouldn't get bent up so fast, I would have recommend using a stock-style 4.0L air box and use a hose as an inlet. I'm not trying to get you to fab up some snake-like intake and I never said anything about it. I'm just trying to express what is going on in the background with the IAT and the timing control. Holy crap........
 

Belizeit

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City
River Ridge
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La
#12
Sorry I opened up that can of worms for you ! My 84 CJ came from the factory I would say with a cold air intake. Hose on the right side of the radiator just behind the headlight to the air cleaner on that crappie amc carb. Not there now, Webber carb sucking in hot air. When I put my new engine in, in the future with some type of FI , I wifi try to get cool air back. Just saying :)
 

bigwalton

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#13
My bad I guess but it was the “SMH” comment directed at the very thing I installed and posted about. I install something and someone posts “SMH” about it? Sorry if I took that wrong.

There is no chance in the world to get a stock TJ/XJ airbox in my engine bay, thought that would be clear from my photo. The filter may look huge, but it’s half again as small as a stock airbox.

I have the donor XJ power distribution center on my driver side fender in addition to the dual diaphragm brake booster and OBA manifold/switch, there is no chance of getting anything short of a snake-y setup or snorkel otherwise.

Belizeit, yes, there’s the air inlet on the other side for the stock intake, but that side also has the exhaust header, to my thinking, unless you’re able to fashion something enclosed that uses that opening (no chance for me) you’re at least canceling out any “cold” air, if not taking in even hotter air.
 

bigwalton

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#14
Maybe it helps to explain that the filter is floating in space, not above the fender, the only open area on this side is between the A/C (OBA) compressor and the grille support. The brake booster and donor engine PDC take up the entire fender.
 

CJ7Pilot

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Yuba City
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#15
... there’s the air inlet on the other side for the stock intake, but that side also has the exhaust header, to my thinking, unless you’re able to fashion something enclosed that uses that opening (no chance for me) you’re at least canceling out any “cold” air, if not taking in even hotter air.
I moved that stock inlet over to the passenger side (right side, for me). The mounting holes are already there. I just need to find a hose that will adapt my GM air cleaner to the AMC cool air fitting.

BW, I think that mod looks good, and I always wanted to do something like that with my CJ7!

If I were to try to "cool air" that setup, I'd try using some PVC pipe to make a housing around the air filter, then find a hose to adapt it to the fitting behind the headlight.

Only you can really see your space limitations though, and time constraints are an even bigger issue.

In all, I think you've got a great setup! :cheers:
 
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mysunnshine

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Phoenix
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#16
My bad I guess but it was the “SMH” comment directed at the very thing I installed and posted about. I install something and someone posts “SMH” about it? Sorry if I took that wrong.

There is no chance in the world to get a stock TJ/XJ airbox in my engine bay, thought that would be clear from my photo. The filter may look huge, but it’s half again as small as a stock airbox.

I have the donor XJ power distribution center on my driver side fender in addition to the dual diaphragm brake booster and OBA manifold/switch, there is no chance of getting anything short of a snake-y setup or snorkel otherwise.

Belizeit, yes, there’s the air inlet on the other side for the stock intake, but that side also has the exhaust header, to my thinking, unless you’re able to fashion something enclosed that uses that opening (no chance for me) you’re at least canceling out any “cold” air, if not taking in even hotter air.
So why can't you mount a stock air box on the fender on the other side?
 

bigwalton

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#17
There is no way to add anything around the filter (unless I swap a much narrower filter I guess). The all-thread support will position the filter within about 1” to 3/4” of both the grille support and A/C compressor. In the photo, the filter is just resting on the A/C compressor, so it will have to come up some.

I wonder now about moving that fitting and maybe trying to bend up some sheet metal to at least direct air from it toward the filter. Kind of a half-assed replacement for the “heat shield” from the kit that I can’t use. Could be a shield for belt water spray as well but I’ll have to see what space I have after getting things mounted. Might end up looking like bad HVAC ducting :rotfl:
 

FLCJ8

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Palm Bay
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FL
#18
There is no chance in the world to get a stock TJ/XJ airbox in my engine bay, thought that would be clear from my photo. The filter may look huge, but it’s half again as small as a stock airbox.
Not to throw more fuel on the fire, but what are the chances of a YJ or Zj air box fitting on your passenger side? :shrug:
 

tower210

Scrambler Junkie
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Olathe
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#19
Not to throw more fuel on the fire, but what are the chances of a YJ or Zj air box fitting on your passenger side? :shrug:
Is a ZJ or YJ passenger box smaller than an XJ? I might have room on the pass side. SORRY for hi-jack
 

FLCJ8

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Palm Bay
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FL
#20
Is a ZJ or YJ passenger box smaller than an XJ? I might have room on the pass side. SORRY for hi-jack
I'm not sure of the difference in the size of the boxes.
However, it depends what you mean by "smaller".
The ZJ filter element is shorter but wider.
The YJ filter element is narrower and marginally shorter.

Both of these boxes are on the driver's side of LHD vehicles.
I said "your" passenger side to BW as his is RHD.
Sorry for the confusion.

I don't know that either would work, (I plan on finding out whenever I swap all my ZJ parts to my Scrambler).
I would think the YJ has a good chance of working as the grill/fender/hood is very similar to a CJ and he has a 4.0.
 
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