CFD testing confirmed what we saw in preliminary testing during 2016. A properly designed elbow on top of the existing intake design far outperforms and has much better distribution than a fabricated top on a cut down version of the BE LS manifold.
What makes these elbows so effective? It's simple. The tighter you try to make a bend the greater the restriction is in that bend. Just like when you kink a hose and it flows less water, the same applies to air passing through and elbow. The tighter the bend, the more boost it will take to make the same power, or the other way to look at it is the bigger the bend the less restriction is created and the more power you will make for a given amount of boost.
For reference sake this is explained in the link below. Whilst the engineering here is targeted at ductwork, the same principles apply to elbows.
What does this tell us in simple trerms. You want the CLR (Center Line Radius) in a pipe bend to be as big as possible to reduce restriction. These engineering principles are what we applied to designing these elbows.