Air Intakes and Filters

There are many options for CAI or air intake upgrades for the XJ/MJ.   We can't list them all but here some random articles and useful links to help you decide:

Many people have ran the K&N FIJK but removed it after seeing how much dirt gets into the engine.   
If you want to replace the K&N air filter cone with an Amsoil dry filter, use the following part numbers:

  • EAAU3090-EA for the 9" long cone
  • EAPF21-EA for the 9" prefilter
  • EAAU3050-EA for the 5" long cone

 
K&N RC-4690 Filter Cone (for XJ 96-01)

Product Style: Round Tapered Universal Air Filter
Base Outside Diameter: 5 in (127 mm)
Flange Inside Diameter: 3 in (76 mm)
Flange Length: 1.25 in (32 mm)
Flange Type: Centered
Height: 7.875 in (200 mm)
Top Outside Diameter: 4 in (102 mm)
Top Style: Metal
Top Material/Finish: Chrome
Filter Material: Cotton Gauze
Flanges: 1
Filter Re-Oiling Amount: 1.66 oz (49 ml)
Weight: 1.2 lb (0.5 kg)
Product Box Length: 6.38 in (162 mm)
Product Box Width: 6.38 in (162 mm)
Product Box Height: 11 in (279 mm)
 
Other Amsoil Filter PN's
Amsoil EaAU4090
Product Style Round Tapered
Base OD 6"
Flange ID 4"
Flange Length 1.75"
Flange Type Center
Media Height 9"
Top OD 5"