Are there any better Intake Manifolds for the 3.8's? If so this means we could use bigger TB's can't we?

 

I don't know about better,but fwd cars with the 3800 II have a different intake manifold, but the fwd intake has clearence problems in an f-body

the stock tb is also huge on the 3.8, 65mm no need for a bigger one
i've seen kits for the supercharged 3.8 to use ls1 tbs tho