cash68

Hi all. I have a 78 350 SBC, that originally had water jacketed cast iron manifolds. The water (i believe) originally went in the exhaust manifold, then came back out, then somehow go dumped into the exhaust going through the prop. They look like this:



I'm switching to OT stellings headers. These have a water log under the headers, with 4 tubes that feed the main jackets, and a water exit in the rear. What should my hoses look like once they are installed, ie, where do I pull the water from on the medusa like maze of hoses on top of the intake?

Young Performance

You should have (4) 1" hose coming out of the thermostat housing. 2 of them are a bypass to keep water flowing when the thermostat is open. The other 2 move water that has flowed through the engine when the thermostat has opened. If this is the way that your engine is configured, then you will need a Y that will reduce the 2 hoses going to each stock manifold into 1. You must have water flowing to the exhaust at all times. Since the Stelling headers only has 1 water hookup, you will need to reduce your 2 hoses to one.
CP Performance sells what you need.

Here is a link to it:
http://www.cpperformance.com/p-12828...e-fitting.aspx

Good luck.
Eddie

cash68

Hrm, not sure. Do you have any pictures of some properly setup Stellings headers? I could just copy the setup if someone has some decent pictures.

fireboatpilot

Let us assume that you are going to block off the factory exhaust thru the prop and go with thru the tramsom tips? Merc sells the plate and "O" ring type gasket for this. Take off those water logs as you called them and flip them around so that the opening is towards the front. This is where you will connect water coming from your thermostat housing cover. As Young said if you have 4 hoses coming off of your therm housing now, 2 of them need to be capped off or better to replace the housing for the proper one. I don't know what type tail pipes you have but there should be a short jumper hose between the header and the tail. The tail will eliminate the "Y" in the system running down to the gimble connection to the prop. I hope that helps?

cash68

What is the blockoff part #? I need to order one, apparently.

Expensive Date

If its the plate I am thinking of you need to pull the motors to get to it.CP performance sells plugs so you can leave the internal prop exhaust in the boat.