MMR cooling head head mod

[K4fxd]

this design comes from the 4.6 from the factory

Please describe what we are looking at in the photo

Sponsored

 

[Kahboom]

K4fxd MMR and other brands are designed off removing the factory freeze plugs, and install a crossover line between the heads for coolant flow, all they did is copy what was done from the 4.6L motors that Ford made from the factory. That's what Jackson1320 posted a pic of.

 

[DrZed]

FWIW... a friend who works on nearly exclusively Terminator Cobras told me in his experience they are more trouble with coolant leaks, and the kit does not provide a benefit. That was hard for me to believe (when I was buying a Terminator) but I trusted his experience.

 

[shogun32]

Well a crossover where both sides are pressurized equally does absolutely nothing.

 

[Jackson1320]

FWIW... a friend who works on nearly exclusively Terminator Cobras told me in his experience they are more trouble with coolant leaks, and the kit does not provide a benefit. That was hard for me to believe (when I was buying a Terminator) but I trusted his experience.

Well a crossover where both sides are pressurized equally does absolutely nothing.

i have the mmr kit and it has never leaked and i don't see any way for it to have a problem unless the installer damages the o-ring.
the kit gives the coolant a path to travel at the back of the head. normally the coolant travels up from the block into the head and out the front. so there's no path or reason for coolant to go to the back of the head so the coolant around cylinders 4 & 8 gets the hottest because the coolant at the back of the heads doesn't move much. now if you open a path for water to flow at the back of the head you have a more equal temp across the head

 

[shogun32]

the kit gives the coolant a path to travel at the back of the head. normally the coolant travels up from the block into the head and out the front. so there's no path or reason for coolant to go to the back of the head so the coolant around cylinders 4 & 8 gets the hottest because the coolant at the back of the heads doesn't move much. now if you open a path for water to flow at the back of the head you have a more equal temp across the head

you put a flow-meter in the middle and also measured pre/post head temps at the back?

Now had they brought the lines back to the front and capped off the OE front return-line or put a plug in them to reduce front flow, THEN and ONLY THEN would there be an actual benefit.

 

[Jackson1320]

you put a flow-meter in the middle and also measured pre/post head temps at the back?

Now had they brought the lines back to the front and capped off the OE front return-line or put a plug in them to reduce front flow, THEN and ONLY THEN would there be an actual benefit.

you don't know what you are talking about. the number 8 combustion chamber does not have a complete water jacket around the top in the cylinder head so it gets hotter then other cylinder so having the water flow out the back of the head has a Benefit also they recommend you take the head cooling mod and connect it to the hose coming out of your heater core. this is connected directly to the water pump making some negative pressure and sucks water through the back of the head

 

[shogun32]

also they recommend you take the head cooling mod and connect it to the hose coming out of your heater core.

except NOBODY has said that and none of the pictures show that. ONLY WITH that change does the mod work at all. Bridging 7 and 8 together does nothing unless there is a pressure differential. The heater-core mod is THE source of that differential.

That said the heater-core line is running at full pressure since it's the output of the passenger side cylinder bank. So the amount of pressure drop isn't very much.

The coyote cooling is just plain wrong.

Ich bin kein Ingenieur, aber ich war letzte Nacht in einem Motel 6

 

[K4fxd]

The heater-core mod is THE source of that differential.

So adding the T and running it to the heater feed is the way? I would then assume you would cap off the factory heater feed line, so the water runs through the block then into the heater then gets returned to the waterpump.

 

[shogun32]

So adding the T and running it to the heater feed is the way? I would then assume you would cap off the factory heater feed line, so the water runs through the block then into the heater then gets returned to the waterpump.

it's a bandaid and a weak one at that. the passenger bank exits the head, runs to the heater core and then comes back to the pump. by tapping the line you're trying to slip extra water into the pipe that is already at 'full rate'. There's some wiggle room and there a 'venturi' effect but you won't get anywhere near full-rate flow thru the back of the head.

The only way to fix it for real is to cap the head exit ports at the front of the engine, and run 2 lines back to the pump.

 

[Jackson1320]

So adding the T and running it to the heater feed is the way? I would then assume you would cap off the factory heater feed line, so the water runs through the block then into the heater then gets returned to the waterpump.

no you allow water to go both ways

 

[Jackson1320]

it's a bandaid and a weak one at that. the passenger bank exits the head, runs to the heater core and then comes back to the pump. by tapping the line you're trying to slip extra water into the pipe that is already at 'full rate'. There's some wiggle room and there a 'venturi' effect but you won't get anywhere near full-rate flow thru the back of the head.

The only way to fix it for real is to cap the head exit ports at the front of the engine, and run 2 lines back to the pump.

It will split the water flow between the front and the back. you have equal flow out the back and the front

 

[K4fxd]

If it really is that easy why didn't Ford do this on the voodoo and predator engines?

 

[Jackson1320]

If it really is that easy why didn't Ford do this on the voodoo and predator engines?

Why didn't they do it on the Coyote? Probably because the cooling was adequate for the horsepower that the engine was making
Now start adding horsepower, adding a tune, adding aftermarket parts, superchargers, and it's not a bad idea to Make sure you're cooling system is up to it

 

[Jackson1320]

If it really is that easy why didn't Ford do this on the voodoo and predator engines?

there's a reason why most ringland failures happen around cylinder seven and eight

Sponsored