Tip & How-To about Jeep Grand Cherokee

Cheapest Real Power Gain For a Jeep with the 4.0 L6

Hello. If you're anything like me, you're always looking to squeeze a little bit more power out of your ride. Whether it be for racing, comfort, or even safety, more power is always better, especially without sacrificing fuel economy, which we all know is a huge factor.

I have a power improvement secret for all Jeep vehicles prior to 1999 (some up to 06.)

If you replace your factory intake manifold with one from a newer Jeep, bam! you get more power. Here are the specifics:

In 1998, when the standards for fuel efficiency were increasing, and the Grand Cherokee was about to debut its newest generation, something had to be done with the 4.0 inline six cylinder that Jeep used across its lineup. It was not going to meet EPA regulations without some tweakage. So, one of the major points of change was the intake manifold.

This is an actual image from my install. The top intake manifold is off of a 2002 Jeep Grand Cherokee with the 4.0. It has been painted with high-heat black. The bottom one is off of my 1996 Jeep Grand Cherokee with the 4.0. Notice the difference in design. The newer manifold is less angular, allowing more air to enter the engine without getting caught up in the manifold. This free flowing design helps free up a few hidden horsepower. For what I paid ($50,) and the increase I felt (upwards of 8hp,) this is definitely the most cost effective, and little known about modification for increasing power in your Jeep 4.0.

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