A strut tower brace is a device which goes between the strut towers of an automobile. It helps to keep parallelism between an imaginary line drawn between the strut towers, and the front cross member. This enhances stability while cornering, and reduces understeer. Sometimes also called a strut tower bar.


                                                                                                                                                                                                                                                                                                            
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A strut tower brace is installed by removing the nuts under the hood at the tops of the strut towers and placing a bracket over the bolts poking up, and by reattaching the nuts. The bar that runs between them is then installed. This should be done with the car jacked up from the front cross member in order to preload the chassis and minimize flexion.

You can also install a similar bar, sometimes called a strut tower brace, sometimes called a shock tower brace between the tops of the shocks in back. These devices do the same thing as a strut tower brace, but of course for the rear of the car. There is a related device called a triangle bar which also runs supports to the floor beneat and between the rear shock towers to add still more support.