Getting funky with our Cobra...
Getting funky with our Cobra is easy with our new Steeda suspension.
When Ford announced that its top Mustang, the SVT Cobra, would get a genuine IRS rear suspension in 1999, the news sent shockwaves throughout the automotive community. While drag racers winced and immediately figured out ways to retrofit a solid-axle 8.8 underneath, autocrossers and open-track fiends finally had their prayers answered with a suspension package that featured robust aluminum lower control arms, forged steel uppers, and adjustable toe links, all wrapped around an aluminum differential that used conventional 8.8 gears. It was a match made in heaven. Well, at least on paper.
When we took our first turn behind the wheel of a pre-production car back in late 1998, we ran it through its paces and it didn't take long to realize something was amiss. Aside from noticeable wheelhop, we quickly concluded that the IRS was lacking in response, predictability, and more importantly, traction, while applying power in a turn. After a few '99 Cobras fell into the hands of several twisty turney racers, the same conclusion was quickly made.
Luckily, Ford heard the cry and in 2003, coinciding with the launch of the much-more-powerful Terminator, it beefed up the IRS. Aside from larger 31-spline axleshafts, the biggest change was the addition of specific rate springs and aggressively tuned Bilstein shocks to control wheel movement. Going up to 17x9 wheels and 275/40/17 tires also helped, but its inherent design was still flawed. Despite the changes that Ford made, it still didn't feel right as the car felt somewhat disconnected when driven hard.
Fast forward to 2008, and we've witnessed a huge step in making IRS Cobras finally work. There are a few companies making suspension components for the '99-'04 IRS Cobras, but based on our experience, few have put together a kit that is comfortable enough for the daily grind, yet competent enough for the track, as well as Steeda has. Now we all know that Steeda is no newcomer to the Mustang suspension market, but when it comes to manufacturing its own suspension upgrades, going to Steeda is like coming home, as you know that you'll get OEM-type fit, finish, and quality.
Getting On Stage
For '03-'04 Cobras, Steeda offers three different G-Trac suspension systems-Street, Competition, and Drag. Since we wanted a more aggressive ride without excessive harshness, we kept things realistic and chose not to put a full-blown competition suspension into our Snake, as it was simply overkill for our weekend play toy. In addition, with our focus on handling, we found no need to go with a dedicated drag suspension because this car has already been running strong with a best of an 11.92 at 118.9 mph.
So, of these three choices, we went with the Street kit, which has components bundled into four complementing stages that allow a Cobra owner to install each stage separately. For instance, you can start with Stage 1, and then add Stage 2 and Stage 3 later. Then if you wanted to, you could finally put Stage 4 in the car a few months down the road. Or you can order all four stages at once, and a complete suspension upgrade can be performed at one sitting, which is how we did it simply because of deadline restrictions.
Starting with Stage 1 (PN 555-2155), we stiffened up our ride with Steeda's boxed steel subframe connectors, three-point tubular steed strut tower brace, billet aluminum caster/camber plates, and Sport Springs, which lower the car a little over an inch. This is often where many people start and serves as the "gateway drug" to better handling and fun on the street.
We then stepped up to Stage 2 (PN 555-2156), which features Steeda's polyurethane IRS subframe and differential bushings, steering rack bushings, heavy-duty antisway bar endlinks, front sway bar bushings, and superfly billet sway bar mounting brackets. For the upper rear subframe mounts, the included reinforcement kit will eliminate a lot of flex that goes on back there.
 Steeda offers its G-Trac Street...  Steeda offers its G-Trac Street suspension in four stages for the '03-'04 Cobra. We decided to install all the stages at once because if we're going underneath the car, we want to do it only once. Here, we see the all-important chassis-stiffening subframe connectors (weld-in) and strut tower brace. |  For our testing purposes,...  For our testing purposes, we went with a set of 18x9.5 Steeda Pentars with a set of Nitto INVO tires spooned on them. We installed the new rolling stock to baseline the car before we upgraded the suspension. We also used a set of NT-555s on the stock 17-inch Cobra wheels. Our baseline was set at 1:24.77. |  For the front suspension,...  For the front suspension, Steeda supplies its Sport Springs, which lower the car slightly over an inch, and include billet aluminum caster/camber plates, offset lower control arm bushings, and bumpsteer-quelling outer tie rod endlinks. Note how the Bilstein struts are an inverted style, which allows a much larger strut shaft to telescope in and out of the housing. This makes for a much more rigid design than your typical Motorcraft piece that will not flex as an assembly under heaving, braking, or cornering. |
 Out back, Steeda addresses...  Out back, Steeda addresses some of the key weaknesses of the IRS. Aside from adding polyurethane bushings to the upper and lower control arm pivots, it also adds stiffness to the entire subframe assembly at all of its attachment points. High-capacity Bilstein shocks and Steeda's Sport Springs bring everything under control. |  To start things off, remove...  To start things off, remove the brake caliper with a 15mm socket and slide off the brake rotor. Next, undo the spindle nut with a 15/16-inch (24mm) wrench, but do not remove it. Using a large hammer, whack the spindle to free this joint, taking advantage of the spring pressure to help pull it apart. Once it is free, remove the ABS sensor with a 1/4-inch six-point socket, and remove the ABS sensor wire's bracket with a 24mm socket. Then, remove the two lower strut housing nuts with the same socket, but leave the bolts in place. |  Remove the steering rack with...  Remove the steering rack with a 15mm socket from behind to hold the bolts and grab an 18mm socket to remove the front nuts. Undo the outer tie-rod ends from the spindle by removing the Cotter pins and castle nut with a 19mm wrench. Free the tie-rod end, disconnect the steering shaft, and slide the rack forward, keeping an eye on the two power steering lines. Now, place a jack underneath the lower control arm on the inboard side and remove the lower control arm bolts with a 24mm socket for the nut and a 21mm socket for the bolt head. The front bolt will slide forward and the rear bolt will slide backwards, but you may need to remove the outboard crossmember bolt with a 15mm socket in order for it to slide out. Lower the jack slowly to relieve the spring pressure. |