What Borla Header will fit my 01 XJ 4.0?

I am lokkign for much better MPG on my 01 i want to replace the whole Exhast system with a Borla Header and probe car back with a Random Technologies Hi Flo Cat. does anyone have any input on this, i keep finding headers for wranglers one that works on 97's then i find more that work up to 99? cna anyone prove a pics and partnumber fo the header thanks and any input on this setup would be great!

This will not increase your gas mileage. If anything it will make it worse being as it's a performance modification. And the reason none are listed for your application; if you look under your hood, you will notice that your exhaust manifold is a two piece design with two o2 sensors on it. Something like the Clifford header is your only real option for replacement, other than a factory piece.

http://cliffordperformance.net/Merc..._Code=CP&Product_Code=57-2015&Category_Code=J

Also, if your XJ is stock, and all parts are up to snuff. It's not really going to get any better, it is what it is.

I did exactly that on my 94, complete Borla exhaust and a Random Tech high flow cat. If you're looking for better mileage, you will *NEVER* pay off that investment.

The best thing you can do for mileage is to keep to 60 or less, and drive like you've got an eggshell under your right foot.

if you are looking for a header for your 2000 or 2001, look at Banks I have read that they have a header for the 2000 and 2001

Semper Fi said:

if you are looking for a header for your 2000 or 2001, look at Banks I have read that they have a header for the 2000 and 2001

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Banks does have a header. I put one in my 01 when I replaced my exhaust system. As for gas mileage I have no idea. I did it all a few years ago so I can't remember and now it's lifted so it's worse regardless. I don't think it got a whole lot better, but it sounds really nice and gives some more power.

Mike

I plan on getting one when I get back from Afganistan in '09. Was it a hard install?

Semper Fi said:

I plan on getting one when I get back from Afganistan in '09. Was it a hard install?

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As far as I remember no, but like I said I installed it a few years ago. I'm pretty sure everything line up and fit nice. I don't think I had any problems with anything really. And stay safe over in Afghanistan, best of luck to you.

Mike

91 Jeep Project said:

This will not increase your gas mileage. If anything it will make it worse being as it's a performance modification. And the reason none are listed for your application; if you look under your hood, you will notice that your exhaust manifold is a two piece design with two o2 sensors on it. Something like the Clifford header is your only real option for replacement, other than a factory piece.

http://cliffordperformance.net/Merc..._Code=CP&Product_Code=57-2015&Category_Code=J

Also, if your XJ is stock, and all parts are up to snuff. It's not really going to get any better, it is what it is.

Click to expand...

There are actually 4 O2 sensors on my '01, 2 before cat, and 2 after the two cats....and they are different part numbers, and different prices, if I remember correctly one was over $100....
and I agree....you won't get GOOD gas mileage PERIOD. The 4.0 is not an efficient engine, Torquey yes, efficient no. One way to get better mileage would be to sell it, and get a newer 4Runner... If mileage is your priority. I gave that up to get the straight axles....and I'm happy, and having fun! Hey, I just drove 4 hours to Mobile, doing 70-80, and got nearly 16 mpg! That's great for me! I'm getting 12-13 round town....3 inches/32's/3.55's/auto.........:moon: