Heidts Automotive solves a unique problem with first-gen F-body Camaros and Firebirds. Owners of the first-generation convertible Camaro/Firebird are familiar with the inherent vibration in the chassis due to the vehicle’s design. The unibody of these convertible Camaros was more flexible due to the lack of roof structure.

GM engineers/designers attempted to overcome that issue with convertible rockers and floors with reinforcement, but that wasn’t enough to prevent all vibration problems. Once these models got up to road speeds, they were subject to oscillation and vibration that increased and decreased with speed.

The factory’s answer to this was to install the now-famous “cocktail shakers” at each corner of the vehicle. These were large cans with a suspended mass on a spring in a viscous fluid that weighed about 25-pounds each.

These “cocktail shakers” were tuned to a resonant frequency to help calm the oscillation by absorbing the vibration energy. Of course, this limited the reverberation for much of the driving speed but not all.

There are several things that can be done to help the situation. New body bushings will help with some of the vibration transfer. If the vibration has steadily gotten worse, check for worn shocks and springs. Replace the worn components as necessary.

The very popular GM F-body convertibles paid for lack of roof structure with an inherent vibration. Photo from Barrett-Jackson.

The Big Fix

Finally, for a somewhat more permanent solution, add some structural stiffness to the frame. Being unibody construction, understanding the stress and flex points of the F-body prevents the home engineer from simply adding more structure. This is where Heidts’ subframe connectors for convertible Camaro/Firebird (par number RC-103) come in to save the day.

The installation of the subframe connectors is easy enough to complete in one afternoon, if not sooner. Simply support the vehicle securely on jack stands then remove the body mount bolt at the rear of the subframe. Only do one side at a time.

Install the connector at the front and replace the lower half of the body mount and washer. Then fasten the connector with a body mount bolt. Moving toward the rear of the connector, remove the 3/8-inch bolts holding the stock leaf spring pocket to the frame rail. Slip the connector’s angle bracket between the frame rail and the spring pocket. Then bolt the connector in place using 3/8 x 1-1/2-inch bolts and washers.

Next, drill a 1/2-inch hole through the frame rail and side of the spring pocket using the hole in the angle bracket as a guide. Place spacer between the outside of frame rail and inside of the pocket. Using 1/2-13 x 3-1/2 bolt and Nylock nut, secure the connector, rail, spacer, and pocket together.

At the front of the connector, drill a 1/2-inch hole through the rear of the subframe and connector bracket, the bolt in place using 1/2-20 x 1-1/4-inch bolts and Nylock nuts. Securely tighten all bolts, then move to the other side and repeat.

For more information on this or the other products made by Heidts’ Automotive, visit them online at www.heidts.com.