thats what i would like to know too. You would think that welding the body would already be rigid enough! guess not.

 

For the NISMO, I think it's the sum of the parts that make the difference. I highly doubt that anyone would notice a difference if they were to remove or add this brace.

I'd rather have it than not have it though. There was mention on the NISMO forum that this brace is bolted on to an area which has very thin metal, so it's level of bracing is in question. Whether the extra rigidity is noticeable or not, I do believe this brace adds to stiffness in some manner.