Our third generation Camaro had come a long way since we picked up the beast for a song and a dance. We have earned major cool points with the car by adding some “attention-getters” to the project car. With a stout Moser 12-bolt rear end, a TCI T700R4 transmission and a set of high performance Weld Racing wheels, our project was rapidly moving up the respectability scale.
Now it was time to think about putting all that torque firmly to the ground without ripping out the stock suspension. Our solution? Simple… call Steve Spohn at Spohn Performance and get some help on how to keep our stock style suspension in place but still handle copious amounts of torque and horsepower. While we were at it, a nice set of QA1 shocks and Eibach Springs for the rear would round up this upgrade.
Stock torque arms were never designed to handle that kind of horsepower and torque. - Steve Spohn
Here’s the deal with F-Body suspensions, the 1982-2002 GM F-Body Camaros and Firebirds use a unique suspension set-up that has only one ladder bar, called a torque arm, in the stock style suspension. The torque arm’s entire job is to prevent the axle housing from rotating. For a daily driver with stock horsepower, this isn’t a problem, but when you go throwing some more power to the equation, the stock torque arms bend, flex or break. This is why you see many aftermarket race suspensions use a four link type suspension system to spread the anti-axle rotation across four bars instead of one torque arm.
“When we first started manufacturing torque arms most ‘fast’ F-bodies were running 12′s in the quarter mile. Then the LS1 F-Body was released and cars started getting in to the 11′s. “As more LSx technology came to market, 10′s and then 9′s were becoming the norm. Today we have customers knocking on the 6′s in some on drag radial classes. Stock torque arms were never designed to handle that kind of horsepower and torque,” said Steve Spohn.
The Spohn Philosophy
In order to keep a stock style suspension on an F-body, the entire load is placed through one single torque arm, which needs to be sufficiently built to handle the torque being applied to the unit. According to Spohn,”what we have found over the years is that the weakest link in an F-Body torque arm is the pinion angle adjuster. If the pinion angle adjuster bends and that link fails, the arm will twist up or snap instantly.” He went on to say, “Our advice would be that if you have an 11 second or slower car with an automatic transmission you’ll be fine with our standard torque arm. If you’re running 10.99 or quicker or have a manual transmission car with an aggressive clutch and do high RPM clutch dumps, then we recommend the Pro-Series torque arm system.”
Based on what Spohn told us, we opted to go with the Spohn Performance Pro-Series adjustable torque arm kit for a 700R4/T5 transmission (Part #301-PS). Spohn told us that they designed the Pro-Series torque arm from a blank sheet with the intent of making a torque arm that could stand up to a “6-second quarter mile. We won’t ever see that speed with our project car but it’s nice knowing that you have the suspension that can.
Highlights of the Spohn Performance Pro Series adjustable torque arm kit:
- Includes the transmission crossmember required to install the 700R4 or T-5 transmission, along with our crossmember mounted Pro-Series adjustable torque arm
- Attaches to the rear axle and controls rear end torque during acceleration, transferring this energy into the tires, increasing straight line traction
- Reduces nose-dive during braking
- Eliminates wheelhop
- Increases sidebite during corner exit acceleration
- Bolt-on system does not require complete interior removal
- Removes the torque arm pivot point from the rear of the transmission to the supplied crossmember
- Changes the instantaneous center and leverage point from stock
- Provides adjustable pinion angle
- No fabrication, welding or drilling required
- Constructed of TIG welded 1.50″ o.d. x .120″ wall (main beams) and 1.25″ x .095″ wall (bracing) 4130N chromoly tubing
- TIG welded 4130N chrome moly threaded tube adapters
- CNC laser cut 3/8″ thick steel rear housing mounting bracket with wide spread
- Heavy-duty fabricated steel transmission crossmember with integral torque arm mounting system
- Del-Sphere front mount version utilizes an extra high strength chromoly Del-Sphere pivot joint for those who demand no bushing deflection and the best in street-friendly bind-free performance and strength
- Rear of torque arm mounts to the 3/8″ thick steel rear housing mount via two 1″-12 NFT x 1″ bore x 1 3/8″ thick chrome moly spherical rod ends with Teflon self lubricating race
- Grade 8, 1″ bolts and 1″ nylock nuts mounting hardware
- Integral 1″-12 threaded 4140 chrome moly pinion angle adjuster between the bottom rear rod end and the bottom rear torque arm tube allows for easy pinion angle adjustment of over 6 degrees
- Unique rotating front torque arm mount (thrustator) system that allows the torque arm to travel fore and aft
- The front rotator tube has an integral grease fitting to allow for proper lubrication
- Rear mounting bracket is designed to fit on OEM or aftermarket rear ends
Adding Respect to Project Respect With QA1 Shocks and Eibach Springs
Now that our Spohn torque arm could handle the load we wanted to get as much performance out of the suspension that we could. Our next stage of upgrade went the direction of a shock and spring upgrade.
Our friends at QA1 have a dedicated section strictly for F-Body Camaros on their menu driven website, which really helps filter down the choices to get exactly what you are looking for in shock performance. We checked with QA1′s Corey Flynn, just to make sure we were on the right path. “With the Moser rearend and beefed up torque arm, our Stocker Star single adjustable shocks will help get the most out of your setup. You can simultaneously change your compression and rebound with one knob, choosing from 18 valving options, which will allow you to use the single dial to adjust to any surface you want to race on,” said Flynn.
Features of the QA1 Stocker Star adjustable shocks (Part #TS704):
- Made in the U.S.A.
- Easy, Bolt-In Installation
- 100% dyno tested and serialized
- Rebuildable and revalveable by the QA1 factory or QA1 authorized service centers
Installation and Tips
QA1′s Stocker Star single adjustable rear shocks are almost fool-proof to install but there are a few tips that should be adhered to whenever you install new shocks. A quick check of the car’s chassis will reveal any other problem areas that you should fix at the same time as your shock replacement. Look for worn out bushings, ball joints and other routine consumable components that can affect the vehicle’s ride quality or safety. If anything looks suspicious, now is the right time to replace it. Check the factory compression bumpers (bump stops) are in place and not damaged or missing. QA1, and most other shock companies will not cover damage to shocks under the warranty if the shocks are installed without factory bumpers or the equivalent.
Replacement of the shocks is as simple as lifting the chassis and removing the existing shocks. Removing the wheels provides easier access during the assembly process. Safety is paramount so making sure the vehicle is supported safely is critical. Start installing the new rear shocks by mounting the upper end first then mount the lower end. There should be no modification needed and the car can be lowered to the ground after the wheels have been reinstalled.
With the car fully set on the ground, check the ride height of the shocks and make sure there is plenty of travel in both directions. QA1′s installation notes claim that a good rule of thumb is that 60% of the stroke should be used for compression, so a little more than half the travel distance should be for the compression or down stroke of the shock.
Adding The Eibach Sportsline Performance Springs
According to the folks at Eibach, their sportsline springs lower the vehicle ride height 1.7-inches to 2.3-inches and still gives race car handling because of the progressive rate spring design. We were looking for great handling AND great ride quality at the same time. The Eibach tech support assured us that the Sportsline rear springs (part #4-0138R) achieved the handling we craved by aggressively lowering the car’s center of gravity and the ride quality would be enhanced by the progressive rate springs. Adding to the upped performance and smooth ride, Eibach backs the springs with what they call the “million mile warranty.” We plan on getting as many of those million miles of use that we can.
On The Ground
Once the Spohn Performance torque arm was in place with the the pinion angle set, and the QA1 Shocks and Eibach Springs were installed, we brought the project car down to ground level. Even with the sun baked paint, our car had a change in attitude. The aggressive stance from our performance suspension upgrades had done something to the physce of the vehicle, or maybe it just changed the way we looked at it, but our project car was turning into a real head-turner.