The 'cage work extends forward through the firewall and provides reinforcement all the way to the front of the chassis. This TJ is propelled by one of Jeep's best-ever mills: the 4.0 High-Output inline-six. This 4.0 is stock inside but breathes through a Turbo City intake. A Barnett Performance Products HD motor-mount block-bracket kit keeps the engine in place with zero block or motor-mount breakage. The stock radiator, with its plastic end tanks, was drop-kicked to make way for an all-metal high-flow unit for better, more reliable cooling. All of the smog-control components were left in place under the hood, which means that the TJ gets to keep its street registration and license plate.