Stillen Pathfinder

Nissan's Pathfinder, and its close cousin the Infiniti QX4, are popular rigs. They're nicely built, offer a wide variety of features, and possess acceptable off-road capability for those who hit the dirt. One rub: They are underpowered. All the GM mid-sizers employ a 190-horsepower V-6, and most of the rest of the market has 200-plus-horsepower offerings. Yet the Nissan soldiers by on just 168 ponies and 196 pound-feet of torque from its 3.3-liter SOHC V-6. It's not that this isn't a worthy powerplant, but despite its nice driving habits, there just aren't enough beans.

Stillen to the rescue. Race driver Steve Millen earned a fine record behind the wheel of track-bound Nissans (and Datsuns) over the years. While his Stillen Motorsports concern now develops and sells performance hardware for all sorts of nameplates, he's still most closely associated with making Nissans perform. Steve and his gang have come up with a straightforward, cost-effective bolt-on kit to bring the Pathfinder/QX4 powerplant up to snuff.

Instead of pricier alternatives such as turbo or supercharger, Stillen engineers went the traditional hot-rod route, focusing on improving the intake and exhaust tracts while leaving the engine internally stock. The system employs new mandrel-bent intake tubing and a K&N high-flow, reusable air filter that draws cool air from a protected compartment inside the fender; the tubing is black-powder-coated for durability and good looks. Stillen also replaces most of the exhaust system with components of its own design and manufacture. The headers are constructed of 151/48-inch 16-gauge steel tubing, and ceramic coated. The stock catalytic converter is retained, but now followed by a cat-back exhaust of larger-than-stock 3-inch mild steel tubing and a high-flow muffler. The system is then aluminized, and finished with a stainless steel tip.

Dynamometer tests evidence a peak increase of 25 net horsepower, and an improvement of 18 pound-feet of torque, according to Stillen. Though we did not witness the dyno runs, the power increase is evident with the first run through the gears. The power curve is noticeably improved in the mid-range, especially in the 2500-4000-rpm range. Power seems to carry a bit further, as well, the Pathfinder still accelerating to 5000 revs.

Some aftermarket exhausts are louder than most "family type" sport/ute buyers would like them. The Stillen system seems right on for the performance-oriented buyer, though it may still be a wee bit vocal for the luxury-minded QX4 driver. It emits a V-6ish burble at idle, the tone stays relatively deep through the revs, and it's all but inaudible at freeway speeds. The hint of intake roar under hard acceleration isn't unexpected due to the open-element air filter.

The Stillen Power Package (part number 503200) is 100 percent bolt-on and retails for $1163. Each item can be purchased separately, though combining the intake, headers, and exhaust as a system provides the max benefit. It's cost effective, sounds cool, and delivers much needed performance.

SourceStillen/Steve Millen Sportparts714/540-5566www.stillen.com