BIGSLVRXJ
NAXJA Forum User
- Location
- Des Moines, Iowa
Dunno if I can call this a write-up but I got bored so I figured I'd tap into my wealth of useless information for anyone that cared. I've had (I think) 3 of the 4 different "models" of airboxes in my 1990 4.0 XJ. Here are some of the differences.
1987-1990-these have the ports for the CCV and charcoal canister as well as two small ports at the back. One of the small ones controls the motor for the door at the front of the box and the other one IIRC is tied to the emissions system. They also have the port at the front for the preheater tube running from the exhaust manifold. Wire clips are used to hold the lid onto the actual box itself.
1991-1995-the two small ports were deleted at the back as well as the preheater tube port and the motor/door at the front. The charcoal canister port also was moved up closer to where the air tube from the throttle body connects. Metal clips and tabs replaced the wire clips to hold the lid onto the base.
1996-I think this one existed for a year, I may be wrong and in 96 it may have been the same as 97+ units. The charcoal canister connection was deleted because it was moved directly to the intake manifold. The CCV port was moved to a more straight across position from the front CCV fitting on the valve cover. The thing is...I believe the air induction snout that pulls the air in was still long for the old body style. I'm not all too sure on this though.
1997-2001-for this year the intake snout was shortened for some reason. I have no idea why but I'm currently using the base of this airbox with the lid of an older one. The snout falls about 1.5" short of where the old ones protruded through the front body brace (or whatever that is) and is diagonally cut. I assume in 97+ XJs they must have moved that brace panel back for some reason (again no idea why) that's why the change was made.
As I mentioned earlier, I'm using a 97+ base with a early HO lid. I have the 97+ lid so I eventually plan on routing the charcoal canister directly to the intake manifold.
Some other things to know...
1. Any air box base will physically bolt up to the floor of the engine bay.
2. Renix air boxes will not work (without modification) to the HO models and vice versa.
3. If you move the charcoal canister line directly to the intake manifold you can put a 96+ lid on an earlier HO base.
4. With a GDI open system radiator they all have trouble fitting and clearing the filler neck.
1987-1990-these have the ports for the CCV and charcoal canister as well as two small ports at the back. One of the small ones controls the motor for the door at the front of the box and the other one IIRC is tied to the emissions system. They also have the port at the front for the preheater tube running from the exhaust manifold. Wire clips are used to hold the lid onto the actual box itself.
1991-1995-the two small ports were deleted at the back as well as the preheater tube port and the motor/door at the front. The charcoal canister port also was moved up closer to where the air tube from the throttle body connects. Metal clips and tabs replaced the wire clips to hold the lid onto the base.
1996-I think this one existed for a year, I may be wrong and in 96 it may have been the same as 97+ units. The charcoal canister connection was deleted because it was moved directly to the intake manifold. The CCV port was moved to a more straight across position from the front CCV fitting on the valve cover. The thing is...I believe the air induction snout that pulls the air in was still long for the old body style. I'm not all too sure on this though.
1997-2001-for this year the intake snout was shortened for some reason. I have no idea why but I'm currently using the base of this airbox with the lid of an older one. The snout falls about 1.5" short of where the old ones protruded through the front body brace (or whatever that is) and is diagonally cut. I assume in 97+ XJs they must have moved that brace panel back for some reason (again no idea why) that's why the change was made.
As I mentioned earlier, I'm using a 97+ base with a early HO lid. I have the 97+ lid so I eventually plan on routing the charcoal canister directly to the intake manifold.
Some other things to know...
1. Any air box base will physically bolt up to the floor of the engine bay.
2. Renix air boxes will not work (without modification) to the HO models and vice versa.
3. If you move the charcoal canister line directly to the intake manifold you can put a 96+ lid on an earlier HO base.
4. With a GDI open system radiator they all have trouble fitting and clearing the filler neck.
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