There is nothing motorsport about them mate. I thought you ment like 909 motorsport.

TBH they are much the same as the next "Custom manifold", none of them have had any real testing done and based more on looks than anything else. "It looks like it will perform really well, so lets just say it does"

So your back to whats the point... EFi inlet is more than good enough for 99% of the cars that we know of.