View Full Version : middle water jacket

06-28-2008, 01:06 PM
I'm installing my heads this weekend and I ran across a thought on my 430cid. Why can't I drill a hole out in my new head gaskets to open up the middle water jacket that is otherwise blocked off? There are 3 water jacket holes in our cylinder heads, but only the middle one is opened up on our block. Why? :rolleyes: Here are some pics to help explain what I'm seeing:


Close up of above pic:


Same water jacket in head:


Close up of above pic:


I mean what COULD it hurt? It would only move MORE water/coolant around in the middle of our head/block area. Isn't that a good thing, better water circulation? :confused:

06-28-2008, 09:14 PM
Sounds like a good idea.

Did you happen to save the original head gaskets to see if they were open or closed? Or did you toss them (like I did)?

06-29-2008, 03:55 PM
Well, mine were not the Ford OE originals, as the O/Owner had the heads and motor already rebuilt. However, I remember they were blocked off as well. I have since thrown them away....

02-01-2009, 10:57 AM
This was never answered fully.

The MEL cooling system is unique in design. It's flow direction is unique and cannot be modified.

The WP injects cool coolant into the block via the diverer openings and the block thermostat openings (four openings total) (block thermostats no longer used). The diverter(s) direct coolant flow up and into the front of the cylinder head. It then flows inside of the head to the rear passage (coolant flow from the cylinder barrels also meets here) and then the flow is directed to the front of the intake with no crossflow whatsoever.

The front passage(s) at the cyl. head and intake is merely a vent. The intake gasket will have a small opening in the front and a large opening in the rear. The reason for the large openings @ the front of the head is for interchangeability of the heads from left to right.

The MEL has no exhaust heat passover provision and heated coolant flow replaces that design.