|
Post by marinetarts on Aug 29, 2013 14:52:35 GMT -5
Hello I'm brand new to this site and also new to the jeep world this is my second jeep and I'm looking to mod it heavy but don't want to swap to a v8. I have a 01 wj with 4.0i6 I'm looking for the best way to gain hp and mpg. So year any recommend brands or parts are very welcome. Lets see where this goes lol.
|
|
|
Post by Halo Performance on Sept 3, 2013 9:53:29 GMT -5
Mpg improvements for the 4.0 get varying results. Start with the easy things, like a tune up and making sure your tire pressure is correct. Go easy on the skinny pedal, too. Skinnier and less aggressive tires may help as well. Less restrictive air intake and filter will help some. Throttle body spacers usually have little to no benefit, but a larger throttle body can net you a little more power. Some people use Dodge Neon injectors for added power, but some people have said there is little to no real benefit from it. Its a Jeep, and about as aerodynamic as a brick, so dont expect 30+ mpg, but i have seen people consistently getting a little over 20.
|
|
|
Post by neil on Sept 4, 2013 5:46:24 GMT -5
Halo has this covered pretty well. You could throw in a good set of headers and low back pressure exhaust. Most of the performance can be had through gear changes though, for the set-up you want to run. You will find that having it geared correctly for the tire size and weight of the vehicle that the 4.0 has plenty of power for wheeling.
|
|
|
Post by yjsaabman on Sept 7, 2013 8:56:03 GMT -5
I have to agree with the above. The 4.0L is the better engine for fuel economy and makes great power to start with. In the WJ chassis you probably have the coil rail directly on the plugs, so there isn't much to upgrade on the ignition side.
A power tuner can really help out once you have the airflow upgrades done to optimize everything. Most of them will also allow you to tweak shift points, shift firmness, and to re-calibrate the speedo and trans to match tire and gearing changes. I think the Superchips brand have been used by other members on here with good results.
|
|
Brian
Moderator
Donator
CSM, U.S. Army
Posts: 1,470
|
Post by Brian on Sept 12, 2013 20:12:00 GMT -5
Adding a cold air intake is an inexpensive way to gain a little throttle response and may or may not improve your mpg...when you price a header, cat back and if legal in your state a hi-flow cat you will also notice some improvement in performance, but minimal improvement in mpg so you won't get much return on your investment...tires really do make a differance. On my '02 TJ, running 35" MT vs. 35" AT tread would cost me better than 1 mpg on the highway and about .5 mpg in town...which transfer case do you have? If your WJ is always in 4WD that will effect mileage too, vs. the Command Trac or Selectrac that allow just rear wheel drive. Unless your exhaust needs to me replaced or your header is craked I would stick with a cold air in take, throttle body spacer for now.
|
|