I've just been reading through the group buy thread for the weapon r intake manifolds and was wondering would I gain anything on my L13 by fitting a cast manifold from the US spec L15 instead of my plastic one?? I've already fitted an intake, manifold, decat and back box and hopefully will be looking at a centre section for the exhaust soon so thought this would be the next step and since I can't afford the weapon r one would a 2nd hand USDM one fit and make a difference??

 

It would bolt to the engine but the TB connection may be different, BUT there would be no improvement in power or performance. It's the same manifold made of different material only.