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3rd Gen Subframe Install - Structural Integrity
We give a T-top third-gen Camaro some much needed stiffening and rear-suspension improvements.
May 29, 2011
Cleveland, OH 44117
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3rd Gen Subframe Install - Structural Integrity
Minus the one small piece we left off, here's the sum of the four kits we got from UMI, installed and ready to go. Some of the other guys in the shop remarked how cool and beefy the new stuff looks, along with improving the visual appearance of the Camaro's underside. If all goes well, we'll have the car track-ready soon.
The UMI subframe connector kit (part no. 2400) is fairly simple to install, even with the required welding. The passenger side connector comes in two pieces to make install around the exhaust system easier. These parts feature heavy gauge box steel tubing, giving any third- or fourth-gen F-body a drastic (and desperately needed) increase in structural integrity over stock.
Before installing the other parts, we wanted to install the new torque arm kit (part no. 2217), since the factory arm was already out of our car. The first step was to support the rear end and body using pole jacks, with the car on our drive on lift. If you don't have a lift, then support the car with jack stands on the body subframe, and use a jack to support the rear. This unloads the rear suspension, necessary for the swap.
Next up, we supported the transmission, then unbolted the factory trans crossmember to make way for the new UMI mount.
Factory (right) next to aftermarket (left). The UMI torque arm mount/relocation kit moves the arm mounting point off the transmission tailshaft housing to the crossmember. With increased power and torque, third- and fourth-gen F-bodies are known to snap tail housings off transmissions when the engine torques violently. The UMI mount features the same adjustability for fitment as the factory unit, and includes a driveshaft loop for extra safety in the event of U-joint/driveshaft failure.
The factory torque arm mount is removed from the transmission and put into the surplus parts pile. To get the mount off, you'll need a jack to lower the tail of the trans so the bolts will clear the driveshaft tunnel.
The new UMI mount bolts up just like the factory one...
...Once in place, all the bolts were tightened up.
Here's the new tubular torque arm, compared to the stamped steel factory piece...
...The difference is pretty obvious, and will provide a drastic improvement for the stability of the rear suspension, along with pinion angle adjustment.
The UMI torque arm attaches to the rear end housing just like the original arm. UMI also sells heavy duty fastener kits with all of its suspension arts, and we highly recommend this cheap option instead of reusing old, and possibly worn out, factory nuts and bolts. Once we had everything in place, all the bolts were tightened up.
We had to loosen the bolts connecting the torque arm to its rear mounting bracket so we could get extra leverage to adjust the pinion angle back to its proper degree. With everything lined up, these bolts were tightened as well.
Up front, the torque arm was attached to the new trans mount using the two included sandwich plates. The new UMI parts feature polyurethane bushings, so you don't have to worry about bushing preload problems. It does help the installation to grease the bushing ends though, and will keep them from binding as the suspension settles in. The necessary grease is included with the kit.
Here's the new forward torque arm mount, bolted in and ready to go. Along with the subframe connectors, this kit also provides extra chassis stiffness, as the trans mount ties into the front body subframe.
After one final check, the driveshaft was reinstalled.
Next up is the new panhard bar (part no. 2037) install. With the rear suspension unloaded (not supporting car's weight) using pole jacks, unbolting the factory bar was ridiculously easy. Two bolts removed, and it came out.
Here's another comparison of factory versus aftermarket. While the original panhard bar is a stamped steel open-sided piece prone to flex under heavy load, the new UMI bar is full tube steel with polyurethane bushings on each end. This bar can also be adjusted while installed on the car, so suspension tuning at the track is easy.
Just like with the torque arm, use the supplied grease to lube up both bushing surfaces, to ease installation and prevent binding of the suspension. Both ends also feature zerk fittings so they can be continually greased after installation.
We set the initial length of the new panhard bar to match the factory one. Then it just slid easily into place using the factory mounts.
With the panhard bar secure, next up were the rear control arms, part no. 2015. If you're doing this install at home with jack stands and a jack, do not support the rear of the car by the rear axle. Remove/install one control arm at a time to prevent the rear from shifting during installation. With the arm unloaded, removal is a simple process of unbolting it at the front and rear of the arm.
With the bolts removed the arm just slides right out. If the rear suspension is unloaded properly, the bolts should easily come out with no binding. If you notice excessive tightness when trying to remove them, stop what you're doing and make sure you've got the rear of the car supported properly and the weight off the rear suspension.
Another comparison: You can easily see the superiority of the new UMI tubular arm versus the factory-stamped steel arm. Again, polyurethane bushing, superior to factory rubber ones, and with zerk fittings for continual greasing and long life.
Installation of the rear control arms is the reverse of removal. If you're installing subframe connectors like we are, don't install the front control arm bolt until after you've slid the rear subframe connector mount into place. The opposite side rear control arm removes/installs the exact same way.
With the connector held in place, we marked the areas where we'd need to grind away powdercoat and expose bare steel for welding. Don't be afraid of the welding part; with the correct equipment it's fairly easy and fun. If you've wanted to learn how to weld, this is the perfect opportunity.
After marking everything off on both sides, we cleaned the area with some degreaser, then hit it with a stripping disc. Once he had a big enough patch of bare steel, we wiped the area down with mineral spirits to make sure it was totally clean for welding.
We used a Lincoln Electric 216 Power MIG welder to secure the subframe connectors in place. Before welding, we also had to strip away the powdercoat on the connectors' surfaces that we'd be welding to the body.
Because we don't know what exhaust we'll be using yet on the car, we left the final connector piece on the passenger side uninstalled to avoid any problems once we've chosen a new exhaust system. This part is designed to install with the exhaust still on the car.
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