GrimmSpeed Strut Tower Brace Red Subaru 2013-2019 BRZ

GrimmSpeed has released the new Strut Tower Brace for the BRZ, which they have spent months collecting numerous data and measuring the performance to develop the perfect tower brace that will work. Laser cut and CNC bent brackets will ensure the perfect fit for the BRZ that installs in minutes with one single tool. GrimmSpeed has used a mild steel construction with a rigid design to prevent unnecessary slop and provide maximum stiffness between strut towers. GrimmSpeed has laser cut their end brackets from 3/16" steel to provide the highest strength and stiffness without compromising thread engagement with the BRZ. Each GrimmSpeed Tower Brace is powdercoated with DuPont textured powdercoating for a unique look without exposure to rust. After installing this product you will immediately feel the improvement in sharpness of steering and feel.

Quick Specs

• Laser cut, CNC bent brackets ensure perfect fit
• Mild steel construction provides maximum stiffness
• Rigid design prevents unnecessary slop and tolerance stacking
• Durable DuPont powdercoat
• Legal in autocross classes that allow a strut tower bar but no other modification
• Installation in minutes with only a single tool

Design

"The GrimmSpeed Strut Tower Brace must provide additional stiffness between the strut towers, enhancing stability and sharpening steering response. We began with testing both on the street and by statically flexing the chassis in the shop. Tweaking the chassis manually and using our FARO Arm to plot critical points in CAD, we were able to identify the weak points in the system. What we 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, we set out to create a clean, simple and cost effective solution."-GrimmSpeed

Using 3D scanned data from multiple vehicles, we were able to quantify the manufacturing tolerances and design our brace accordingly. What that means for you is a perfect fit and easy installation. 3D-printed prototypes helped speed the development cycle and allowed us to test a number of different bracket designs for fitment and aesthetics.

One key design decision was to utilize a rigid, welded construction. The reasons for this are three-fold, but what it boils down to is the old standby, ‘Keep It Simple, Stupid’. When the goal is to reduce compliance in the system, it’s not hard to understand why a solid form design is best.

• A rigid bar will function with maximum stiffness, providing the best possible performance 
• A multi-piece bar adds unnecessary cost and complexity to a fundamentally simple mechanism
• A multi-piece bar adds additional welding and hardware, stacking tolerances and creating many possible failure modes

Materials

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 we’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.

Performance

Performance metrics, both quantitative and qualitative were carefully tracked through development and following production. In GrimmSpeed slalom testing, peak deflection between the strut towers dropped from .180in to .030in, a decrease of 83.3%. Even more notable than the lowering of deflection was the substantial decrease in ‘noise’ within the data. You can truly feel this improvement the first time you leave your driveway after the install. Expect an immediate and noticeable decrease in NVH and a noticeable increase in sharpness and steering feel. Without the brace, the data shows a great deal of noise and unpredictable deflection, indicating an unsettled chassis. After installation of the brace, noise in the data is greatly decreased and behavior is much more predictable. With the brace installed, the chassis reacts as you would expect, cycling between tension and compression as the brace works to maintain stiffness between the strut towers through the slalom.