I feel compelled to share this with anyone with a 2.5L or a 4.0L. I have a 97 wrangler with a 2.5L ran great off the lot a few years back with those car looking tires until I put on some 31 BFG Muds, along with a 2in budget boost. It looked great, tuff, ready to rock. But when i got on the highway my power had decreasesd , it was like i had to drive down wind and lean my body forward. If i turned my air condition on i had to lean a lil more your get the picture. And of course some of us do not have a whole lot of extra cash to thow on our jeeps. Well the trail and error begins on the 2.5L engine. Some of these tips and tricks are well knowing and maybe others not, but remember this is budget time. Of course the first thing i did was throw in a Flat panel K&N filter in the factory box, did feel a lil difference. Next i cut out the front of the factory air box, o much better. Then i saved a few dollars and i installed a accel coil with accel 8mm wires, that were purchased from acmejeepparts.com felt better crisper response. Also added some NGK plus after trying many others these gave me the best results and found that gapped at 0.38 worked best. I purchased the plugs at a NAPA auto parts. Then installed a after market muffler by dynomax worked and sounded great. Still in search of more power i had wished for a complete catback but again minimal funds. So what i did i took a hacksaw and cut the downward elbow off the end of my tail pipe and added just the right stainless steel tip made from a thermo coffee cup. Do not laugh nobody knows and it looks great, but most of all it made one heck of a difference as now any air comming in is exiting much better. Then i purchased a throttle body spacer the kind with the screw design and gained some torque on low end but no gains on highend or freeway driving. Actually my jeep was a little to torquey that it was hard to even drive in parking lots or crawl at slow speeds without jerking around getting whiplash, so i replaced it with one from gsppowerspacers.com they make one that works wonders and power was felt going slow and at highway speeds, what a diference. Then i got a lil brave and bored out my own throttle body with a cordless drill and a small sanding disk. Bored the top side only at first little by little, then the bottom side realy slow little by little. At one point i thought i went beyond the point of now return, because on a lil four banger with to much air coming in or out you will lose torque. Remember torque is what gets a lil four banger going off the line along with its 4.10 gears. I am super happy with all my lil mods to my engine, it now keeps up with any stock 4.0L. I am currently saving for a electric fan from flex-a-lite.com. O yeah did tweak out my factory air box by added a cut mud flap between the engine and filter to help keep warm air out from filter. Also removed the chrome light bezels to allow cold air to ram into the box. One more lil thing there is a hole in the metal fender just above the right shock just below the factory air box. Cut a hole in the bottom of the box to macth the hole in metal fender. Nice cold air oooo so nice. My lil jeep screams now. with its lil 31s and factory 3.10 gears. I hope this helps out my fellow jeepers out there with 2.5L. I could only imagine what this would do on a 4.0L guy on a budget. Cacth your later. Quicksand97
08-02-2009 09:59 PM
Get a 4.0l and you don't have to do all that. Here is a link on why:
I ve read, and heard that 4.0 swap is about 2k, it looks like you already spent that much in your story
good luck with the Frankenstein :)
08-02-2009 10:10 PM
Only problem I see with using cold air from the wheel well while off roading is getting water up there and into the intake? With a snorkel you have a lot to travel before you get to the airbox.
08-02-2009 11:34 PM
Not even close to 2k. It works for now and one day i would love to do a engine swap
08-02-2009 11:41 PM
Yes a snokel for deep water crossing is best. I have had no problems with heavy down pours or splashing thru large puddles at all. Where the shock mounts on the top side it acts as a shield from splashing water getting into the box. As far as deep water i just do not go higher than that point which is about 36 to 37 in from the ground.