I'm not sure if I'm even calling them the right thing...This is a molded rubber tube that carries water to the headers with outlets for each cylinder. The part # is 091889 EBJ80B675 X (I would post a picture but struggling with my phone). A basic google search produced nothing. One of them is cracked and needs to be replaced. They mount to Custom Marine headers on 454's...thanks

This one??? http://www.cpperformance.com/p-14698...uton-tube.aspx

That sure looks close...mine has a molded rubber piece on the end that steps up to a slightly larger diameter for the hose coming out of the thermostat housing.