[DeTomaso] The Water Restrictor Plate Below the Thermostat

[Larry Finch]

All,

A stock Pantera 351C cooling system has five (six with pulley) specific design components in the engine. 

Water pump WITH bypass passage
Water pump impeller WITHOUT backing plate

Restrictor plate in block
 
High-flow thermostat*
Thermostat with “hat”

* I have heard/read multiple times, and have personally come to believe, that the Cleveland OEM thermostat was the high-flow version with the hat.

Tim Meyer (he is the vendor who took over the Todd Buttermore Cleveland project and is now providing aluminum and iron blocks) has retooled the original high flow Cleveland thermostat($32), as Thomas and Chuck have previously mentioned. He also has a proper restrictor plate ($20) ($49-the set) for the block. 160-180-195 versions. 

Personally I have no problem spending $32 to purchase an OEM-correct high-flow thermostat from a vendor who has stepped forward and made them readily available. 

I don’t believe the money saved with a NAPA standard-flow thermostat justifies the restriction to coolant flow that must surely come with that non-OEM style. 

Now in practice, we all know there are many approaches to cooling that will provide acceptable performance. 

Example:

2511 when purchased had the pinhole restrictor plate, a Windsor standard flow thermostat, and the Weiand water pump which does not have the bypass passage. That engine did not run hot, did not boil over; performed just fine year after year. It actually had zero out of the five design components mentioned above.  :-o  ;-)

Maybe the Weiand water pump impeller that has a backing plate increased water flow enough that the standard flow thermostat restriction was neutralized?

Whatever, it worked. 

Perhaps logic, and respect for the original Ford-engineered system, would seem to suggest the standard .... starting.... point for any 351C cooling system should incorporate all five of the above design components.

Then, if you have cooling issues you know that you have at least started with the correct OEM design.

Larry 

Impeller backing plate 
Undersized WP pulley
Single-dual-pass radiator 
160-180-195 thermostats
Brass-aluminum radiator 
Upright or laydown 
And..........and.....    :-)


Sent from me using a magic, handheld electronic gizmo.