I dunno. I think bracing things up has the potential to make a good bit of difference. The unibody is essentially split down the middle by the trans tunnel, which I imagine greatly affects structural integrity. Seems like bracing those two sides together can make a difference.
An S54 Z3M roadster owner I know swears the front strut tower brace he installed made a huge difference.
1998 BMW 328is
1966 Pontiac GTO
2007 Subaru Impreza 2.5i 5-door
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