Aftermarket Control Arms
For All 1983-88 Cougars / Thunderbirds
Page Revised: 10 May 2019
Your Cougar's control arms (front and rear) are made from standard-issue OEM components designed for longevity. As vital suspension components, however, they just can't handle any kind of serious performance driving. And let's face it: with the advancements in Fox chassis performance suspension components in the last few decades, it's really beneficial to upgrade your control arms to something much more modern.
The front A-arms have been a shroud of mystery for a lot of Cougar owners. Let us dispel the rumors: you have Mustang-style A-arms in your car, but it depends on your model year. Here is the conversion you need to know:
|A-ARMS FROM:||ARE THE SAME AS:|
|1983-86 Cougar/Thunderbird||1979-93 (Fox) Mustang|
|1987-88 Cougar/Thunderbird||1994-98 (SN95) Mustang|
Here is a side-by-side comparison. On the left is the shorter 1983-86 Cougar A-arm. On the right is the 1987-88 Cougar A-arm. Note that the later arm is 3/4" longer and has revised points for mounting the springs and the sway bar end link. Because of the different types of stock engine crossmembers used in our cars, it's not advisable to interchange one type of A-arm for the other unless you have replaced the engine crossmember ("K"-member).
The 1983-86 front A-arms used to be available new through Ford Racing (p/n M-3075-A). They featured brand new low friction ball joints and improved inner bushings. However, Ford Racing has since discontinued the kit. Remanufactured or new stock-type control arms should still be available via Fox Mustang websites.
The 1987-88 front A-arms, originally adapted from the rear-drive Continental, have a deeper cup for the spring seat, and a raised section for the ball joint. They allow for 1/2" more travel vs. the earlier arms, meaning better control and ride. Ford Racing used to offer a kit (p/n M-3075-D), which would upgrade your A-arms to 2003-04 Mustang Cobra specs. Again, that kit is discontinued but we've seen them on Mustang restoration websites.
For increased handling and better unsprung weight you can use tubular A-arms meant for Fox Mustangs. They greatly reduce unsprung weight in the front end and give you excellent cornering and control. While not very cheap, the prices of such pieces have come down in recent years and are close to being affordable for the masses. They are really intended to work with tubular K-members but sometimes can be used standalone, depending on the brand. Keep in mind that a lot of tubular A-arms will not allow a stock spring to seat; almost all use coil-over struts. Also, some tubular A-arms do not allow for attaching the stock sway bar. Shop carefully!
Your car has a live rear axle with traditional rear-drive 4-link suspension: two upper control arms and two lower control arms. Changing the control arms has a huge impact on how your car handles, and more importantly, how well your rear axle behaves during hard cornering and spirited driving. The stock control arms are 3-sided with an open bottom and can flex and bend under hard driving. While welding plates onto the bottoms will technically help strengthen them, that's just a temporary fix. Full box tube aftermarket control arms are better, but tubular control arms offer the ultimate in strength and resistance to bending or warping.
Using Mustang control arms won't work for us—we have unique-length upper control arms. Even adjustable Mustang uppers won't give acceptable results. In the past we've had to resort to using GM A-body (Chevelle) uppers because they were close enough in specs to what we need (within .0040"), and they do work well. However, we can now use CHE uppers that are specific to our chassis; see below for more info.
It is possible to use Mustang-length aftermarket control arms on a Cougar/Thunderbird. They are about 3/4" shorter, centerline to centerline, and therefore will rotate the rear end upward slightly, and shorten the overall wheelbase a small fraction of an inch. They'll also increase the pinion angle slightly. While there seems to be no negligible effects of using them, most owners prefer to have the correct length control arms if possible. Fortunately we do have a few choices.
CHE Performance contacted us in late 2004 with the willingness to accommodate our chassis's control arm requirements into their in-house manufacturing. The result is a set of tubular steel control arms, both upper and lower, and the first such arms specifically made for the Fox Thunderbird/Cougar chassis in a complete set. The build quality is excellent, and fit and finish are outstanding. Installation is a breeze. All hardware is included with the kit as well—you don't have to reuse any of your stock bolts. Their stock bushing is an interesting urethane/Delrin design for low friction and no squeaks. It's a good compromise for the street and performance driving. CHE will custom make bushings to fit your driving—if you want a softer bushing for the street, or a harder bushing for the strip, not a problem. You can even have the housings powdercoated in one of several different colors instead of the stock silver finish. And you can get adjustable lowers and uppers for slightly more cost than normal. If you need to order just the uppers, CHE will do that for you. Please use the promotional code COOLCATS during checkout and receive an additional 10% off your purchase. We'd like to hear your feedback about these products as well. Please contact us with your observations.
First on the market to mass produce specific lower control arms for our cars is Maximum Motosports, who is renowned for their Mustang race car wins, both factory-sponsored and individually-sponsored. Needless to say, they know what they're doing when it comes to making killer suspension components. Owners have reported good-to-slighty-harsh ride quality, likely due to the harder urethane bushings used. Handling is markedly improved. All components are of excellent quality. MM offers a few options as well: stock-length tubular (MMRLCA-3.3), or adjustable tubular (MMRLCA-4) to help control ride height. Spring perches and sway bar mounts vary, so be sure to order the correct style for your particular application. Note: we do not believe that Maximum Motorsports offers a compatible rear upper control arm for our cars.
If you're looking into serious traction bars for drag racing, the infamous South Side Machine lift bars really plant the rear end on takeoffs. They bring your rear suspension's imaginary center of gravity to the dead center of the car (instead of a foot in front of your front license plate with the stock suspension). This results in less power lost in the suspension wind-up and more power to the rear wheels. They are not recommended for street use since they give a punishing ride—they are for drag-strip use only. SSM is now part of UMI Performance, Inc. and they offer the lift bars plus rebuild kits for them.