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mustang 05-09 cooling mods

let's see how this goes...
The 05-07 mustangs have a goofy coolant flow scheme, basically the thermostat is on the cool side of the engine, where most thermostats are on the hot side. The problem with this (well one of them) is that the temperature is always "delayed" or inaccurate, if the gauge reads 230, chances are it is actually 240 or 250 where it counts. This was remedied in 07 by the rerouting of the coolant and a different coolant crossover pipe. While it would be easy tochange to this system, the issue is that there is no resource for the 07 to 10 coolant crossover, Ford global parts no longer has them I tried with salvage yards that serviced the entire north american continent with no luck and the aftermarket does not provide a source either, so, unless you happen to be right there when someone trashes an 07 to 10, you can't get the coolant crossover, it simply does not exist.
This is the solution..
Here is a pic of the coolant routing.

20221108_104627rad stuff.jpg

What we are going to do is restrict the water flow to the heater, and either by using an orifice, or a 160 degree thermostat, we are going to regulate the flow through this system. The orifice is brain dead simple, but may require some experimenting, the 160 stat is only available from Mishimoto (that I'm aware of).

part0(4) orifice.jpg
So that takes care of the big hoses, now on to the heater hoses.
You will need these parts


You will need to modify this part of the tubing

So it looks like this, the hose is a bit of a PITA to force over the fitting but it will go. Inside the fitting place a washer
( stainless) With a 1/4 inch hole. This will force the heater water to flow through the rad instead of just looping, and it will cut down on high pressures inside the heater core at high rpms..
All of this is located under the intake manifold, which is really not that hard to remove. This whole procedure should help with cooling, but you also need to interrogate the ECM and lower the fan temp to 170 degrees.


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OK, part 2.. radiator fan mod
so there is a problem with the fan wiring in some of these cars, the resistor causes problems along with corrosion, so we will take that project on as well.first off disconnect the battery, and dig out the fuse box, this is what you will probably find. The burned contacts are to the fan motor wiring.


notice the burned contacts, the solution to this is to remove those wires from the box and reroute them,also cutting out the resistor.
C1035C is the grey connector, pins C12 and F12:
C1035B is the white one, A12 and C11.

MFE5P77dHoGrayrgpins 2.png

white pins.png

So the scheme is to make it look like this, you do have a couple of options, one is to just rely on the coolant switch to turn on the fans, the other is to provide a toggle switch so that they can be turned on manually as well.

Screenshot_20221109-131658_Samsung Notes.jpg

Screenshot_20221109-131654_Samsung Notes.jpg
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So.. changed out the fan relays today, disassembling the fuse box and pulling put the correct pinned circuits gets us here. The large wires go to the high and low speed fans, the smaller wires are the PCM/ trigger wires that activate the relay.

I then located some fused relays which looked good on.paper but in reality, muddied up the waters, since they only would protect the fans and not the relay or the PCM " trigger" wiring.20221117_110650.jpg

So, in the pre mentioned wiring diagram, you can see that the entire relay is dependent on that 40 Amp fuse, the issue is that the same 40 Amp fuse protects the " trigger" wiring, which is woefully too much amperage, or in my case the trigger wiring is not protected at all. So.. the wire going from the fuse box to the trigger wiring was separated and fused with a 5 Amp in line fuse.20221117_164357.jpg
The 40 Amp fuses protect the fan circuitry from the relay out20221117_164446.jpg

The new wiring diagram now looks like this..
Now both the fan circuitry, the relay and the PCM/ trigger wiring are all protected with reasonably practical fuses.
Soldered up the new wiring harness and was done.
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Pulled the intake, replaced to tubing with the above mods, while I was at it, also a good time to replace the heater hoses and those POS snap in fittings20221122_133937.jpg
Also ran the Dremel I used to cut the fittings off across my thumb for added


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