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1970 Plymouth Super Bee - Bars and SpringsA new suspension for an old dog From the July, 2007 issue of Mopar Muscle By Randy Bolig Photography by Randy Bolig
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One of the things that Mopar musclecars are well known for-besides winning races-is the use of a torsion-bar front suspension. Instead of employing a coiled spring, like Ford and G.M., that supports the weight of the car by resting in a spring pocket and exerts pressure on the lower control arm, Chrysler's torsion bar was a far departure from that idea, but we don't need to tell you that. What we do need to tell you is, that no matter how good something is, there is always a way to make improvements, and there is an alternative for Mopar musclecars. Let's preface this article by saying there is nothing wrong with the torsion-bar suspension in a factory car, but where do you draw the line? When do you realize that a torsion-bar suspension may be outdated for a particular usage? When we started laying out a plan for our '70 Super Bee, we knew we wanted to do a modernized adaptation of a B-body. Sure, a stock resto has its place, and those cars are cool, but building a car that can handle in the corners, stop in a shorter distance than a football field, and still pound the quarter-mile in less than 11 seconds has definite appeal. Mopar's factory torsion-bar... Mopar's factory torsion-bar setup is a good suspension for a stock car that is being driven as intended. But if you add 21st-century modifications to the rest of the car, then why not do the same here? So that's what we are planning to do. This month, we will show you what it takes to install an AlterKtion K-frame with rack-and-pinion steering, and coilover shocks to replace the torsion bar. We're not going to stop there-we will also install a tilt steering column to add to the "21st century" appeal. We know you want to know how it works after it's installed, but as you look at the car, you can see it ain't gonna be running for a while. We're in the mock-up stage now, but as soon as we get this car done, you can bet they'll be a lot of track time involved, including some with corners. The AlterKtion unit has several benefits over the factory K-frame and torsion bars. For starters, the kit is roughly 100-plus pounds lighter, and removing the torsion bars and steering box makes more room in the engine bay; it's actually a lot stiffer/stronger than the factory K-frame. This job is really not that hard if you are mechanically inclined. But remember, if you aren't sure you can remember to tighten every nut and bolt, or you are just not sure about tackling a project like this, you better farm it out; it's better to be safe than sorry. It only took working a couple nights to complete the install. the only time we needed anything more than a hand wrench was when one of the camber bolts had rusted fast to the upper control-arm bushing, and we needed a flaming hacksaw.  You have to remove the k-frame...  You have to remove the k-frame and suspension to do this swap. In a nutshell, remove the torsion bars, unhook the upper control arms, disconnect the brake lines, and then remove the four bolts holding the k-frame in place.  A slight coat of black helps...  A slight coat of black helps so you can really see what we're doing.  The factory bumpstop brackets...  The factory bumpstop brackets will need to be removed. Blair tools have a large assortment of these cutters in different sizes if you need.  The "drill" cuts around the...  The "drill" cuts around the factory spot welds.  After you remove the bumpstop...  After you remove the bumpstop brackets, you'll need to grind the remaining weld off.  The AlterKtion frame is held...  The AlterKtion frame is held in place by the factory bolts in the factory locations.  A little grease on the bushings...  A little grease on the bushings helps keep things from squeaking later.  The kit comes with all the...  The kit comes with all the bushings and hardware needed; simply slide the lower control arm bushings in place.  Both connection points of...  Both connection points of the lower control arm get end caps for the bushings, and then a large Grade-8 bolt runs through the lower control arm and frame unit. The set screw in the middle is to ensure the bolt shaft can't come out. Just another feature that Reilly Motorsports incorporated for added safety.  The shock tower on the outside...  The shock tower on the outside of the framerail are a snug fit, but again, with an eye on safety, the kit comes with these plates that help support the shock tower from the inside.  Simply drill two holes through...  Simply drill two holes through the framerail using the shock tower as a guide. Put the two bolts through the shock mount, through the framerail, and then through the bracket. Just make sure not to overtighten the bolts.  You'll need to assemble the...  You'll need to assemble the shock unit, but that's simple. The area for the shock is also able to accept Air Ride bags if you plan on doing that. In our case, the adjustable coilovers are fine.  The spindles are modified...  The spindles are modified Mustang II units. They're easy to source, and work well with the forward-mounted rack-and-pinion steering. Plus, everyone has a disc brake setup for Mustang IIs. You can go from fairly stock to full-blown race applications.  The upper control arms are...  The upper control arms are fully adjustable.  The rod ends are screwed into...  The rod ends are screwed into the control arm, the recommended amount, and then they simply install on your stock Camber bolts using the supplied spacers.  The finished top-side of the...  The finished top-side of the assembly.  For our application, we chose...  For our application, we chose to use a nonpower steering rack. Reilly Motorsports also has a power unit available as an option. The rack simply bolts on the back side of the cross tube.  The tie-rod ends and adjustable...  The tie-rod ends and adjustable coupler are now installed on the rack. It's a good idea to put anti-seize on all the threads when you are assembling the kit. The tie-rod end goes on the bottom side of the steering arm.  Here you can see the rack...  Here you can see the rack installed, and the sway bar on its way to being installed. The sway bar mounts to the front of the frame unit, and the end links are tabs welded to the lower control arms.  Since the spindles are Mustang...  Since the spindles are Mustang II pieces, the factory Mopar brakes will not work. We've had good luck with Stainless Steel Brakes products in the past, so we decided to use them again. first, install the caliper bracket.  Next, make sure to pack the...  Next, make sure to pack the bearings for the rotor, install them and the seal, and mount them to the caliper. Remember, do not overtighten the bearing nut.  Now just put the brake pads...  Now just put the brake pads in the caliper, slide it into the bracket, and attach it with the supplied hardware. We are not running the brake lines yet, as this is all for mock-up before paint and body.  With the factory column out...  With the factory column out of the car, it's time to mount our Flaming River tilt column. This is a fairly simple project. If the area around the column at the firewall looks familiar, that's because the factory firewall mounting plate for the factory column fits the Flaming river piece.  Inside the car, we had to...  Inside the car, we had to do some modifying.  The Flaming River bracket...  The Flaming River bracket held the column too low under the dash.  Some simple cutting with a...  Some simple cutting with a bandsaw fixed the problem.  Now we just turn the bracket...  Now we just turn the bracket upside down and remount it.  Before you finish mounting...  Before you finish mounting the steering column, have a buddy help you make sure that it's neither too far into the dash or too far out. One thing you can't see in any of these pictures is the absence of an ignition switch on the column, where it should be for a '70. we plan on installing a kill switch with a pushbutton to start the car. No key required.  The engine needs to be mounted...  The engine needs to be mounted in the car before we begin to connect the column to the rack-and-pinion. Reilly Motorsports has dedicated engine mounts for their k-frame, and on some big-blocks, the boss near the mount may need a little modifying in order for the mount to fit.  Once the mounts are installed,...  Once the mounts are installed, just drop the engine in place. Make sure the car is level before you begin. Once the car is level (as checked on the door sill), you can then level the engine.  Talk about room, the headers...  Talk about room, the headers literally fell into place. Now, you can mock the steering up around the engine and header.  Once you find out how long...  Once you find out how long a piece of steering shaft you need, start putting it all together. Remember, the shaft must not protrude into the universal joint. Keep it flush on the inside. Also, it's a good idea to dimple the shaft at each spot where the universal's set screws make contact.  Here you can see the finished...  Here you can see the finished shaft. Do not have any universal joint working at more than a 35-degree angle, and if you have two universal joints, ALWAYS put a steering shaft support bearing in between them.  There you have it-a complete...  There you have it-a complete modernized Mopar front end. Stay tuned as we work on the rear and get this thing rolling.
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