Our base model Barracuda is no exception. Since this car didn't have the boxes installed from the factory we called the Paddock and had a set of aftermarket torque boxes delivered. These torque boxes resemble, though aren't identical, to the factory units, but when installed it's hard to tell the difference. They do, however, brace the forward leaf spring mount exactly like the originals. An added benefit in our application is the torque boxes are located under where the main hoop of the rollcage will go, increasing safety by preventing the rollbar from punching through the floor in the case of a rollover accident. Installing the torque boxes is a breeze. Our torque boxes fit well with minimum amount of trimming required before welding the units in place. A welder, clamps, and metal grinder were the only tools we needed to complete the installation.
We used clamps to hold the...
We used clamps to hold the front of the frame connector for welding and a floor jack to hold the rear in place. Be sure to apply enough pressure to hold the frame connector in place, but don't lift the car from its level position on the jackstands.
With our subframe connectors...
With our subframe connectors welded in place, it was time to trial fit our torque boxes and mark the areas to be welded. Our boxes fit with a minimal of trimming on one side.
Once fitted and marked, we...
Once fitted and marked, we again clean the metal in the areas that will be welded with a grinder.
Subframe connectors were never installed from the factory, but are probably the best investment you can make in your car to decrease body flex and add rigidity. The floors in most Mopars are actually part of the car's structure, linking the front and rear subframes together. This theory works well as the floors are certainly strong enough for the average passenger car, but adding an engine with tons of torque will tax the sheetmetal floors beyond their intended limits. Floors that are rusty or have been repaired may not have the integrity of new factory floors, which only adds to the problem. Adding a framemember to connect the front and rear framerails is basically like converting your unitbody car to a fully framed car. The steel tubing doesn't replace, but rather works with the floor structure of the car to add rigidity to the vehicle. An added benefit-and this is a worse-case-scenario-is in the case of a collision from the bottom of the car (car rolls on its side and is hit by another car or hits the wall) the frame connectors have significantly more strength to resist an impact. We hope we never have to test this, but it does add significantly to the safety of our race car. Safety aside, the most noticeable benefit of stiffening our bracket car will be shown in our timeslips. A car with a stiff frame will react quicker and more consistently than a car that flexes, giving us the ability to fine-tune reaction times and accurately predict elapsed times, both very necessary components of bracket racing.
A good welder is the key to...
A good welder is the key to performing frame work, such as adding torque boxes and subframe connectors. We're not really professional welders, but our Lincoln mig welder made the job easy.
Our torque boxes are welded...
Our torque boxes are welded to the car's rear frame, floor, and rocker panel, which are all different thicknesses requiring multiple voltage and wire feed settings on our welder. By following the recommended settings, we made decent, though not perfect, welds.
Remember all cars are manufactured...
Remember all cars are manufactured a little differently, so the torque boxes may not be an exact fit. By welding small portions, the torque boxes were heated up, making them easier to form to the car's frame with a hammer.
Our research of frame connectors led us to one of the leading providers of frame and chassis components: CompetitionEngineering. We chose their premade, bolt-in frame connectors because of their close tolerances and good fit. Bolt-in frame connectors are a good choice in a street car or a valuable original car as they can be removed easily to give the car its original appearance. Since our car is a dedicated race car, we'll be welding them permanently in place for even more rigidity. The bolt-in units fully encompass the rear framerails of the car and give plenty of area to weld, adding significant structural integrity to our car. Like the torque boxes, the only tools we needed were a welder, grinder, and clamps. The subframe connectors took a couple of hours to install, and other than welding, no special skills were required. If you don't have a welder or want to be able to remove the connectors, you'll need to drill holes in the car's existing frame to bolt them in. Either way the installation is fairly simple and will greatly improve the rigidity of your car. All things considered, subframe connectors are probably the best and most economic way to stiffen your car's structure.
Once welded in place, you...
Once welded in place, you can see the aftermarket torque boxes aren't exact replicas of the factory units, but they do accomplish the same goal of stiffening the frame in the area of the forward leaf spring mounting bracket.
Our torque boxes were bare,...
Our torque boxes were bare, untreated steel, so once welded in we gave them a quick paint job to prevent rusting.
With our new components welded...
With our new components welded in place and painted, our job is complete. The torque boxes and frame connectors do add weight to our race car, but the extra rigidity they give us will be well worth a few pounds of extra weight. Our car will be stiffer, safer, and more consistent through the elimination of chassis flex. Not bad for a day's worth of work!