Z4C...attempting to go from write-off to race car

[Vanne]

Do it, see how you go, not telling you not to do it. I'd be keen to see real world data for it too. Worst case scenario, you can re enforce them when/if you start seeing cracks. Plenty of examples of the front towers cracking/deforming on the web. At any rate, un less your pushing pretty hard I doubt you'll see any issues, I am also unsure that it would be lighter?

 

[Liam22]

Regarding rear strut towers, only BMW will have done the calculations to determine if they can handle all of the body loads. Aftermarket suspension manufacturers don't. Also remember that loads depend on spring rates, tyres, unsprung mass and "shock loads" such as running kerbs.

Reinforcement plates are available cheaply. They're the same size as E30, E36 and E46. They effectively increase the thickness of the damper top mount to resist deformation.

A strut brace will have the same benefit (for front and rear) if they surround the top mount and use the same bolts as the top mounts themselves.