Recommended Modifications

[Zeke]

Hey All,

just bought a 2000 XJ. Looking for any recommended mods (under $200 total) to improve performance, mileage, hp etc... I had an 88XJ with Rusty's air tube - thinking of doing that again. Any thoughts on plugs, etc? This will be an everyday vehicle as well as my touring car for the woods of Maine and New Hampshire...

Thanks

Z:cool:

[ChuckD]

IMO, I would leave it alone other than routine maintenance. I have read good things about Champion and NGK plugs. Save your money for future mods (armor, gears,lockers, wheels, tires etc..), if you decide to go in that direction.

[btl_fed_xj]

About the only upgrade's you could go with would be K&N cone filter with an air tube and perhaps a header or new exhaust. Definitely add something on there because once you do it won't be long before you want to add more and more things on to your XJ.

Best of luck to you!

-Jamie

[andyr354]

ya, save your money. None of the mods make much difference at all.

Putting on a low restriction exhaust may actually make your milleage worse since a 4.0 gets better low end torque with some back pressure. (been there done that)

Air filters are a waste of time, unless you wan't better filtering and then get an amsoil foam element. It does flow better, but unless you are running 4K rpm+ all the time you will never know.

It will also run the best with the champion plugs it came with, plenty of threads in that on the group as well. I bought some splitfires on closeout and it idles rough with the stupid things so will be taking them out.

Put that $200 towards an SYE instead.

Andy

[LawlessXJ]

That six cylinder airpump under your hood will benefit from a less restrictive air filtration system. But to really see the most significant benefit to your top end it needs to flow better in, through and out. All that won't do much to improve your grunt for grinding over difficult trails at 2 mph. But it will help compinsate for all that stuff that you add to the XJ that's great for wheeling but bad for keeping up with the freeway traffic.... all depends on what direction your heading with your ride.

Add what you want and have fun doing it, ya gotta start some where especially when you got some spare buckage burning a hole in your pocket. :)

[ChuckD]

Then I say take that $200 and apply it to armor, or even better good tools, then you can fab your own stuff. The amin thing is deciding what you want out of your XJ.

[Lucas]

Or replace the stock shocks with more durable units that fit your driving needs

[Eagle]

I agree with Chuck. $200 won't buy many different modifications or accessories. For the use you described, I would leave the engine, ignition and intake all stock and start by investing in armor. I'd go first for a gas tank skid, because your year has a plastic gas tank back there. If you get lucky and score that for well under $200, next stop should be either transfer case skid or rock rails. Transfer case skid would cost less, and is more critical from a functional (rather than cosmetic) perspective.

[BLUTO]

I bought O.E.M. engine and TC skidplates for under $100 total from the dealer! Now, these may not be 1/4" steel plate like some of the aftermarket ones; but if you are not going to be wheelin' in torturous conditions, then they should suffice. I think the gas tank skidplate was ~$190?
I would also invest in some better shocks, OME shocks with your stock springs should really help out in the comfort-handling department ;) !

BLUTO :)

[GreenGhost]

Don't forget to armor the interior of your rig as well. Pick up some nice floor mats that'll keep your carpets lookin' good. Maybe some seat covers while your at it. Pick up a first aid kit and fire extinguisher. Think about settin' up some tow points front and rear. The XJ is a capable rig as is. Take your time and stay on this board. There's always tons of great ideas floatin' around. Soon you'll have a picture of just what you want (though it's likely to always be evolving), and you can concentrate on saving up for mods that'll let your XJ do the kind of wheelin' you want. Pardon me if I started sounding like Stuart Smalley there at the end. Call it Zen and the art of XJ modification.

[RyanT]

Whoever said you won't notice a difference in putting on the intake tube and K&N ... is well, flat out Wrong you will notice substantial (IMHO) throttle response increase... for about $60 total Rusty's Offroad (http://www.rustysoffroad.com/performance.html) . You could get a BB for $100 or you could make your own. Then there are the things that you can do yourself, like bore your throttle body Go Jeep's Webpage (http://www.go.jeep-xj.info/How%20to1.htm) (did mine with a Dremel)... it makes a difference in throttle response as well.

[XJguy]

K&N is a waste of money and your engine. I have read at least 4 independent tests that show that a K&N flows no better than a new paper element filter. In two tests it actually flowed worse! K&N filters allow way too much silt into the engine, this will eventually ruin it, bottom line (no pun intended, but it does do havoc to those main bearings). I know from first hand experience. The only time a K&N is better is when dirty. The reason being that a K&N has so many huge gapping holes in the gauze that even when stuffed with filth it still flows relatively well if compared to a paper filter with the same amount of dirt...but at what cost? Remember, race cars use them because they get rebuilt after just a few races, some racers actually use no filters at all..get the picture?

You can make a homemade air tube with a heat shield using some PVC tubing, barbed hose fittings, and some sheetmetal that will be better than anything currently on the market and it will cost you about $12. If you want to insulate it add a few more bucks to that. A huge paper conical filter will cost about $20 by Purolator.

$200, save for a SYE as suggested.

XJguy

[bill hitchcock]

if you want some more horse power get a cam shaft for like 140. its the only mod you will notice any horsepower gain that is under 1500 bucks

[Craig Wood]

I would look to buy some good nerf bars (ie. ORGS). A little more than $200.00, but an important item. Hope this helps.

Craig

[eric91xj]

In my opinion if your are'nt racing your XJ and it is just a daily driver with mild offroading then i would'nt worry abotu any performance add on's until you lift it and get into the 31"+ tire range. For mild offroading your XJ is pretty capable in stock form, but for $200 you could add some sway bar dissconnects, front tow hooks and brackets and some factory skid plates from a junk yard or dealer and you will be opened to a whole different world offroad just with these items.

Later,

Eric

[Judd W. VA]

Whew, many controversial replies!!

Using common sense and from the looks of the K&N filters they have to be at least as good as paper in filtration ability. Cannot 'see through it' as well as some paper ones. Banks (that really big and successful turbo company?) includes them in all their turbo upgrade kits as well as others. Occasionally hear of this problem, but have yet to see any real world verification. As a matter of fact, just was into a '91 Nissan SER for a timing chain that has had a K&N for 200,000 miles and was zero cyl bore wear. This would be the first place that would be affected by intrusion. I just do not believe the bad press. More and more companies are also releasing essentially the same products- How could not oiled gauze not do a better job catching grit?? I do ocassionally re-oil the elements that are in use in all my vehicles.

Don't even think about touching the cam. These later ones are hardly modifiable in that department with the system/emission restrictions.

The little 4.0 DOES come alive with intake and exhaust mods. Yes, low end torque will be negatively affected but generally where more power is needed is in the mid to mid-upper RPM range. Also been there, currently doin' that on my '98. The increased power for pulling mountains or towing at speed is way better even with my stock 3.07's. Fuel mileage has surely not been negatively affected and has increased when the engine has to be pulling hard, ie., is not not fighting system restrictions.

For that little of money i would do the filter upgrade and replace that honkin' large restrictive muffler with A Borla or Flowmaster 50 Series.

[THE_OWL]

One word:
N I T R O U S
then some ground effects