Advanced Engine Management (AEM) Inc. wasn't messing around when its engineers set out to design the Brute Force Air Intake System for '97-'02 Jeep TJs. Using the technology behind its established street systems, AEM already had a good basis for what type of performance gains it expected to get out of the Jeep 4.0L engine. One difference, however, is that in the search for horsepower, the engineers still paid close attention to maintaining and increasing low-end torque. This resulted in a very trail- and street-friendly intake system and easier breathing for the Jeep TJ.
The AEM Brute Force Air Intake System features a CNC mandrel-bent 6061 aluminum intake pipe that's individually tuned in both length and diameter for maximum power, is powdercoated, and uses TIG-welded fittings and brackets. Efficient air filtration is achieved through use of AEM's lightweight urethane four-layer cotton-gauze filter that features a redesigned air horn that's said to make an additional 1-3 hp when used with an AEM system.
The Brute Force system is pending C.A.R.B. exemption (50-state legal) and comes with complete installation hardware, detailed instructions, and an AEM decal and license plate frame. The system is manufactured in the U.S.A and requires no drilling or modification of factory components for installation.
We installed one of the first Brute Force systems manufactured on our Project TJ and were immediately impressed with the increase in performance. Highway and commuter driving benefited greatly, offering a 75 mph cruising speed at 3,200 rpm with plenty of pedal left to bring it to 80-85 mph while still under 3,500 rpm.
Low-end performance also hopped up a good deal, with excellent pedal response for planting extra torque to the ground for bumping over trail obstacles and steep hill climbs. AEM promised a better breathing engine with its Brute Force Air Intake System. Not surprisingly (and thankfully), it has provided.