With the release of the new 2015 S550 Mustang, Steeda knew that addressing the IRS system would be a top priority. Being the first production Mustang with an IRS since the 03/04 Cobra's, we knew there would be a great opportunity to capitalize on Ford's new piece by giving it the Steeda advantage. As with any suspension system, deflection is an issue if it's present. Anytime a piece is moving, twisting or vibrating when it should be stationary is a major problem. One of the areas team Steeda wanted to focus on was the rear IRS subframe.
As you have seen with our IRS Subframe Bushing Support System, it limits the movement of the subframe by filling in the voids of the OE bushings. With Steeda's IRS Subframe Support Braces, we have taken the S550 rear suspension to another level!
Our Steeda S550 Mustang Rear IRS Subframe Braces for 2015+ Fastback coupe Mustang 5.0L GT, 5.2L GT350, 2.3L EcoBoost, and 3.7L V6 fastback coupe (non-convertible) is built in-house from 4130 chrome moly steel and powdercoated silver metal flake, this part isn't only strong - it also looks great under your new Mustang! What we did was tie together 3 very important points on the S550 chassis. We utilized existing threaded holes in the rocker panel (the strongest part of the body) and connected that to the front mounting location of the IRS subframe and the rear mount of the lower control arm and toe link. Connecting these 3 points together not only adds rigidity that was lacking in the rear, but also more control of the whole car.
Also, unlike competitors kits that have not been released yet and only replace the factory bracket, our Steeda kit supports that bracket while connecting to 2 additional locations, therefore providing twice the support! Best part about this kit is it uses all existing holes in the chassis so the car doesn''t have to be modified in any way and adds no NVH whatsoever.