tSurprisingly, there is still a plethora of disco-era Camaros (late-second generation) running around on the dirt tracks of America. Dirt trackers have been wrenching on these F-body Chevys for decades, there are still some tips and tricks that can help racers get through the corners faster. In factory stock and street-stock classes, it is all about carrying momentum all the way around the track. We hit up the experts at Speedway Motors and AFCO Racing to help us showcase the basics for our readers.
Chevrolet’s second-generation F-body cars were produced from 1970 through 1981. The unibody structure, with front subframe, A-arm front suspension, and leaf springs to control the solid rear axle, have always fit into the dirt track rules and budgets. They have been getting a little more costly lately, but there are still some “experienced” chassis at each track that are available for a decent price tag.
Where To Start: The Front Suspension
When it comes to A-arm front suspensions, the importance is usually placed on the length of the upper A-arm, and rightly so. For most entry-level “stock” car classes, an adjustable upper A-arm is not allowed. That doesn’t stop builders from using stock parts to get a more favorable camber angle in the front tires. There were at least three different styles of upper control arms used in the Camaro and Firebird between 1970-1981. The three different styles are interchangeable as far as mounting is concerned. The 1974 through 1980 style is slightly longer than the other two styles. These work perfectly on the left (driver’s) side.
AFCO Racing’s Ben Baker suggests getting the upper and lower control arms stripped and blasted, then powdercoated or painted with a good high-temp paint that will hold up and protect the control arm. After stripping, and before coating, there are a couple of steps to prep the control arms. If you plan on using the control arm shaft, Baker also recommends, “Make sure the upper control-arm shafts are straight by either rolling them on something flat or spinning them in a lathe.” A plate of glass works well for checking straightness of cylindrical parts by rolling them on the smooth surface.
A steel-bushing upgrade will help these control arms better react to dirt-track racing. Baker recommends a pair of AFCO Racing Steel Rear Upper Control Arm Bushings (PN 20098), and a pair of Steel Front Upper Control Arm Bushings (PN 20099) for the improvement. Binding is the concern in a race suspension, switching to steel bushings and getting correct shaft alignment will help minimize these issues. “You will have to drill the inner bushings on the lowers, out to 9/16-inch, along with your lower control-arm mounts, if they are not done already,” said Baker. “If your holes are too big or elongated, then you will need to weld ½-inch flat washers over the holes and drill them out.”
Proper Spindle Alignment, Hubs, Brakes, And Linkage
Baker suggests running a straight rod through the lower bushings to ensure proper alignment. If there is any misalignment, then binding could be a problem. It is a good idea to repeat this procedure with the upper control arms. Finding and fixing misalignment conditions prior to installing the cross-shaft is critical to success.
Getting the correct horizontal pivot points is important, but don’t overlook the vertical-shaft pivot points for alignment. Allstar Performance makes a tool to check the spindles for ball-joint alignment. This tool uses two, tapered-steel studs that go into the ball-joint bosses on the top and bottom of the spindle. A rod runs through these hollow studs to check the alignment of the spindle. “You will probably have a hard time finding a stock spindle with the proper alignment,” says Baker. “There is a way to fix the problem if you have the proper equipment, but for the most part, you just get the best you can and roll with it.” For the record, the Allstar Performance Spindle Checking Tool is listed as part #ALL11176 on the Summit Racing site.
The upper ball joints are bolt-in components, while the lower ball joints will need to be pressed in to the lower A-arm. “Sometimes, the mounting holes have elongated or gotten larger from wear,” said Baker. “You may have to tack-weld the lower ball joints in place.” Baker also reminded us to check and pack the wheel bearings, or buy new ones if needed. “If you want to have the absolute best, there is a process to have the bearings polished for lower drag,” he advised.
It goes without saying that — at a bare minimum — the brake hubs or rotors need to be turned. Baker advises to get new ones, especially if the current hubs are older. Install new brake pads and replace the idler-arm, tie-rods, and drag-links with new ones. You’ve gone this far, don’t cheap out with linkage that may be bent.
This era’s Camaro suspension is fairly simple and bolts together without any issues. Choosing the right parts and “fabbing” a couple of shackles will get the rear planted where you want it. Baker recommends having a supply of different-sized lowering blocks to help get the proper ride height and wedge settings.
When it comes to the leaf springs, Baker obviously recommends AFCO’s 176-pound rate multi-leaf spring (PN 20228) with the wrap-up reinforced front segment on the right rear. Speedway Motors offers similar choices from different brands:
- Hyperco #11340 composite leaf spring with a 175-pound rate.
- Landrum #21-340SPD multi-leaf spring with a 175-pound rate.
- Speedway #91721340 multi-leaf spring with a 175-pound rate.
For the left rear, Baker suggests the AFCO 205-pound rate multi-leaf spring (PN 20228HDRF) with wrap-up reinforcement. Speedway Motors has alternatives for this leaf spring as well:
- Hyperco 11342 composite leaf sping with a 200-pound rate.
- Landrum 20-342SPD multi-leaf spring with 200-pound rate.
- Speedway #91721342 multi-leaf spring with 200-pound rate.
While stock shackles will work, Baker said he has seen many racers fabricate stock-appearing shackles that are usually 2-inches longer that seem to work better. He states the stock bushings in the front eyes of the leaf springs work well with no issues. The preferred bushing for the rear eyes of the leaf springs and the chassis are bushings made with Delrin. These can be milled at home or sourced from shops like Detroit Speed. “Make sure to use locking nuts when you bolt the springs on, and do not over-tighten the springs. If you over-tighten the springs it will cause the suspension to bind,” he advises.
In most street-stock and factory-stock classes, the rules state that the shocks used must be a non-rebuildable type of shock. That generally limits what can be used on these cars. Baker recomends a full AFCO setup with #1020 on the left front, #1021 on the right front. If you find you need to tighten up the car or need more forward bite, using a #1022 on the right front will help. The rear shock setup is a little more user friendly with #1032 on both sides. If the track slicks up, switch to a #1034 on the right rear. There are many other options when it comes to shock manufacturers, but we recommend to stay with the non-rebuildable, big-body, steel, mono-tube shocks with this chassis setup.
- L/F: #1020
- R/F: #1021 or #1022
- L/R: #1032
- R/R: #1032 or #1034
Weight And Balance
After everything is installed and tightened, the car can be rolled on the ground to set the frontend settings. Baker suggests setting the right front for second gen Camaros to 3.5 degrees of negative camber, and 3 to 4 degrees of positive caster. He recommends setting the left front at 3 to 4 degrees of positive camber and 1 degree of positive caster. Move to the front of the car and measure the toe settings. According to Baker, you will want to get as close to 1/4-inch toe out at the front. Double check all the settings and adjust as needed. Keep checking and adjusting until no adjustment is needed.
When all of the frontend setting are stable, you can roll the car on the scales to check the wheel weights and get a look at the corner and side-weight percentages. Baker also reminded us, “keep the rear wheels in line with the front wheels, and move the right-rear wheel inboard if needed on dry tracks.”
Starting Set Up:
- 50lbs wedge
- 3-inches of rear stagger
- 55-percent rear weight
- 53-percent left-side weight
If all of that is within limits, or close, check the ride height of the front end. Put the car on jack stands and pull the front springs out. Check the bumpsteer. According to Baker, if you have used a stock-style rod-end on the spindle, “it is harder to fix the bump, but it can be done. If you use a bearing-style rod-end on the spindle, you will use spacers to adjust the rod-end away from the spindle to get your bumpsteer correct.”
Obviously, there are a great number of variables that apply to chassis setup, ranging from tires to track surface. This setup should give you a great starting point. Remember to keep good notes and try a few tweaks here and there as the track and weather changes. Keeping good notes will allow you to duplicate the setup when you get back to that condition, or allow you to go back to the previous setup if things get worse after a change.