For years, the Jeep 2.5L inline four-cylinder engine returned yeoman service in base model CJ, YJ, and TJs. The little mill, while never a powerhouse, was reliable and produced good low-end torque for its displacement. I had written about a YJ project back in 1995 that I called, "The Little Engine That Could" because it worked so well. Its drawback was its bell housing bolt pattern, which matched the old GM 2.8L V-6. The transmissions that mated to this bolt pattern were sub par in every way. Many aren't aware that in 2003 Jeep changed the engine in low trim model Wranglers to the PowerTech 2.4L double-overhead cam, 16-valve four-cylinder that produced about 30-percent more horsepower and torque than the old 2.5L did. The 2.4L had the 4.0L's bell housing bolt pattern, so the new four-cylinder Wranglers shared the same trannys as their 4.0L siblings. That means stronger, reliable transmissions were available for the four-cylinder TJ.
Dan McKeag, owner of Burnsville Off-Road, and I were talking about the excellent four-cylinder Jeeps we'd owned and he commented he had one with the 2.4L and a 42RLE automatic overdrive transmission sitting in the yard. This was no junkyard dog. It had only 8,900 miles on the odometer and was like new inside and out. This sounded like a project in the making.
It was. Dan had his crew at Burnsville Off-Road go to work and turned this four-cylinder Wrangler into a competent backcountry trail vehicle. Not a budget build, the Wrangler uses some of the very best off-the-shelf parts available today. Check out the photos and see what was done.
ARB's larger air compressor...
ARB's larger air compressor fits perfectly on the driver's side TJ battery tray.
An Optima Yellow Top battery...
An Optima Yellow Top battery handles starting and deep-cycle winching well. The Optima can even be mounted upside down, though Burnsville chose to mount it in the normal fashion.
The compressor and rear ARB...
The compressor and rear ARB Air Locker is controlled by ARB switches that fit neatly in the center stack.
Currie Enterprises' new F9...
Currie Enterprises' new F9 Ford 9-inch housings were used front and rear. They look different from Currie's 9 Plus series of 9-inch housings that are great when doing a resto rod or street rod, because the classic 9-inch look stays true to factory. Some, though, need heavy-duty 9-inch housings for hard off-road use and Currie's new F9 fabricated 9-inch housing is extremely strong and beefy to meet the requirements of buggies, competition rock racing, or hard-core off-roading. Built with heavy wall plate and 3-inch, 0.250-inch wall tubes, the housing can take an unbelievable amount of bashing. It's designed so rocks slide off or under the angled pumpkin. The F9 is also available in other configurations to match your needs. Currie's heavy-duty drag link and tie rod steering kit is a must-do TJ addition. A Teraflex steering box skid protects a PSC steering box. The Old Man Emu 2.5-inch coils are supple and give just the amount of lift needed to clear 33-inch tires.
The PowerTech 2.4L DOHC, 16-valve...
The PowerTech 2.4L DOHC, 16-valve four-cylinder produces about 30 percent more power and torque than the earlier 2.5L did. It sits on JKS motor spacers that raise the mill 1-inch to work with the Currie Enterprises 1-inch body lift.
A Vanco hydroboost power brake...
A Vanco hydroboost power brake system was installed to help the TJ stop, and stop it does. While the 33-inch tires don't require a hydroboost to improve braking, the advantages offered by the Vanco unit make it a great addition even with the smaller tires. The pedal pressure required is greatly reduced and brake modulation feels fantastic. The hydroboost is a hydraulically-operated booster and master cylinder and runs off the power steering pump. Naysayers told us that, "Hydroboosts don't work because you can't steer when you're applying the brakes in vehicles with pumps not designed for them!" Nonsense. When we drove the TJ that still had its stock power steering pump, we noticed no difference in the steering when braking. The only difference was the superb braking. We'll go so far to say that if Vanco makes a hydroboost kit for your vehicle, get it!