Hello Jeep JK owners and those who are curious about Supercharging a 3.8L V6.
As you know, the Jeep JK lacks power in stock form. This is especially noticeable when you add aftermarket accessories such as steel bumpers, a winch and larger tires. Compound this added weight with coolers filled with food and drink, camping equipment and two adults, you get one sluggish Jeep.
Basically, you have three options to resolve this scenario:
1. Do nothing and be content with the sluggish performance of your Jeep.
2. Modify the OE powerplant with aftermarket accessories to gain some much needed horsepower and torque.
3. Swap in a more powerful engine. (Hemi or similar)
Each of these options have positives and negatives.
Doing nothing will keep your new Jeep covered under the dealer's warranty, but all your buddies will laugh as they pass you in their modified vehicles on steep grades.
Upgrading the OE powerplant will net some usable results-not a lot, but enough to get you back into the passing lane on long hillclimbs.
Swapping in a larger displacement engine is costly and can create issues when it comes to emissions and warranty.
So, what's a Jeeper to do?
Chrysler doesn't have a real solution in the Mopar Performance catalog. Nor does a Jeep dealer offer any type of fix for the under-powered JK.
We're on a mission to see what the best solution is for this problem.
Our resident project JK, the Silver Bullet is a 2007 Unlimited model with a well broken-in V6.
We tested a Superchips FlashPac programmer and found that it provided a little more pep for everyday driving. But we wanted more.
We modified our exhaust with a high-flowing glaspack style muffler. Results were less than impressive.
The RIPP stage II kit retails for $4,799.95, which isn't exactly cheap, but adds a claimed 111-HP to our manual transmission configuration and comes with all the necessary hardware and software to make our JK feel like we think they should have from the factory.
It took Jeff Arabia and his crew at Overkill Jeep Fabrication eight hours to perform the installation while we snapped photos.
After the install, the rig was much more responsive from 3,000 RPM on up to the 5,500 RPM red line.
We began our testing with 50,383-miles on the odometer.
We've run the vehicle in all types of terrain from the slick rock trails of Moab, to the sand dunes of Pismo State Beach. The supercharger has not let us down once.
We've towed several different trailers with the unit installed and found much in the way of useful power band. On long steep grades, the Jeep is able to accelerate past slower big rigs, which make it fun to drive.
Around town, the supercharger makes quick work of stoplight to stoplight challenges by unsuspecting challengers. We would compare it to the acceleration found in a fullsize SUV such as a Chevy Tahoe with a 5.3L V8.
Getting up to speed on the freeway is now one of our favorite aspects of driving the Silver Bullet.
The vehicles MPG improved as well:
Before: 10-12.5-MPG around town, 13-14 on the highway.
After w/supercharger: 12.5-14 around town, 14-15.5 on the highway.
Stay tuned for a full tech review in the coming months inside Four Wheeler magazine.