GrimmSpeed Strut Tower Brace - BRZ/FRS

You’ve probably read somewhere on the internet that a strut tower brace never does anything but look pretty. You’re about to read otherwise. Armed with a strong background in vehicle dynamics and chassis design, GrimmSpeed spent months understanding the BRZ/FR-S chassis, testing different designs, collecting data and measuring performance. With the help of the FT86Club community, they’ve developed a strut tower brace that works.

Their design requirements for this project were simple. The GrimmSpeed Strut Tower Brace must provide additional stiffness between the strut towers, enhancing stability and sharpening steering response. They began with testing both on the street and by statically flexing the chassis in the shop. Tweaking the chassis manually and using their FARO Arm to plot critical points in CAD, they were able to identify the weak points in the system. What they found was interesting. The OEM triangulation bars actually function very well. So, while the allure of a beautiful 3-point brace was tempting, the data spoke loud and clear: a simple 2-point brace was the right solution. With that, they set out to create a clean, simple and cost effective solution.

End brackets are laser cut from 3/16" steel and precision CNC bent. These brackets were sized to provide maximum strength and stiffness without compromising thread engagement with the vehicle. Cross tubes are CNC laser cut to length from .125in wall tubing. Mild steel, being both the viable material that is both economical as well as the well-suited for the job, was an easy choice. Contrary to popular belief, mild steel offers greater stiffness than stainless steel and while stainless steel offers higher yield strength, in this particular application, we’re nowhere near those types of forces. The assemblies are all robotically welded in the same fixture for unbeatable accuracy and repeatability. Each finished brace is coated with a durable DuPont textured powdercoating. The cherry on top, so to speak, is that they’ve laser cut the GS logos from stainless steel, so you’re free to polish the coating off of it for a unique look without worry about rust.