Meant to take a photo while I had it out, but forgot in my rush to get the engine running late last night .

There is a rubber gasket that seals the TB to the intake plenum and it has a partial copper grill mounted to its upper half (part# 22271-75031). The grill is roughly the shape of an inverted 'U' with center maybe 1/4 the gasket diameter and legs maybe 1/3. The gasket is at a mild downward angle on the TB side top/end of the plenum (and flush to the TB). I'm interpreting it as a diffusion grill, perhaps for the purpose of slowing the upper TB air flow where it enters the plenum, or perhaps for something else?

Does anyone have any specific knowledge of what that grill is intended to accomplish? Has anyone tested intake/engine behavior with Vs without it (the grill, that is, not the gasket)?

Any helpful info appreciated !

Thanks -- Trevor

PS. I also posted this question in the xB2 forum, however, it has been installed in the 1G tC a lot longer than the 2G xB, hence the repeat.

 

I think they use it to do what the gmc vehicles mass sensors with the honeycom. that helps smooth out the turbulat are flow and make it more direct i guess you can say. not 100% on this one but it makes sence if that will help smooth the air for the plenums