From the factory, every LS engine has a steam vent system which is a couple of hoses and fittings that come from the top of the cylinder head’s water jackets and connect into a port on the radiator. The idea is that these ports allows air pockets to escape the cylinder heads so that they do not create an air lock that can keep water from flowing properly through the cooling system. It’s a simple system, but very effective. Unfortunately, some people try to eliminate this system which only makes their life harder that it needs to be.
In this video you are going to see the ROY Garage do a Trick Flow steam vent kit installation. There are lots of aftermarket options that look cool and create clearance for aftermarket intake manifolds, and they all install pretty much the same. If you are looking for a nice kit, this Trick Flow kit will do the trick, and right here you can see just how easy it is to do the install.