As many of you may know the intake temp steadily rises when you are going slow
The main reason for this is the poor airflow of the inter-cooler radiator

For those that just want the mod jump to the end of the post

As some background I have done a lot of testing on this both with the stock coolant pump and the upgraded 010 pump

First the pump differences
Heat soak is about the same but with the 010 pump slightly sower to rise but quicker to fall. The main diference noted with the change to the 010 pump was the lowest temps recorded. with the 010 at speeds above 90kph the IAT (intake air temp) will come down to AAT (ambient air temp) with the stock pump it will get within 3 degC at best

Cooling performance
0-50Kph Nil, you can run all day at these speeds and never see the temps go down by more tha 1 or 2 degC
50-80Kph temps start to come down
80KPH, temps start to come down quickly
90KPH, its really efficient from here on up

Air Flow Mod
My First test was just with the bonnet down and letting the heat soak happen.
AAT was 28DegC and I let the IAT heat soak up to 41DegC
Once I got to this position I removed the PWM signal to the engine fan
This turns the fan on full blast
IAT temps started tom come down right away dropping 2 Deg in the first minute

Now this is no way as fast as going at 80Kph but the key is its dropping
It took a full 11 Minutes to drop the temp to 3DegC above AAT

In the first pic "testing" you will see how I ran the fan at full blast
The 3 connectors you can see are located (clipped to) the washer bottle
I took the pic from uder the car

To get to them
1. Remove the cover plate next to the fog lamp
2. Remove the under tray

If you put your hand through the cover plate opening you can grab oneside of the plug and get the other side from underneath

The Mod
This is in 2 parts Part 1 is the 10 minute mod and I have done this for testing only

1. From the "Testing" Pic you need to cut the white wire
2. Wire in a horn relay connecting one end to pin 30 and the other to 87A
A horn relay has 5 pins rather the the usual 4
The extra pin is 87A and is a normally closed pin
In other words pins 30 and 87A re connected when the relay is off
3. This step is up to you but I chose to trigger the realty using the fog lamp power
I never uses these an it makes for a good switch to tuen on the fan at the lights

You can see this in the second pic. I took this before wrapping up the harness
The connector on the lower left is the fog light plug
This is wirired to the turn on the relay
The pulg on the top left is the one for fan and the 2 wires are leading back to where I cut the plug from the harness
I have used a plug socket to connect the relay to this (plugs on the right) so the bumper can come off when needed.

Bigger Mod (Auto control)
This is a bit more tricky
What I have done is add a Voltage triggered Switch. This is connected to the MAF sensor.
Here is a link to the kit Universal Voltage Switch - Jaycar Electronics

What this does is turn on a relay when the voltage falls to a preset level.
My MAF reads 1.48V at idle so i have it triggered here
The next thing is this kit has a hysteresis setting.
Ie it tuns on when volts fall below a set voltage but does not turn off till it get a second higher voltage setting
I have this set at 1.57v which roughly equate to 1500 rpm

So the net result is the fan comes on when you stop and goes back to normal when you hit 1500rpm

The next step is to remove the relay trigger from the fog lamp and trigger it from the the voltage switch.

Some may have noticed I used a 3 pin plug when modifying the fan harness
The green wirs is a 10A fused 12v power.
This wire goes to the voltage switch to power the unit
The relay output for the voltage switch connects to the 2 white wires

This has eliminated the relay in the pic

The next step is stopping the voltage switch at speed. For now I have added a 15 second delay to the relay trigger
12V Power ON Delay Relay Module Delay Circuit Module NEW | eBay

This stops the fan being triggered till im at adle for at least 15 seconds.
This is stop the fan turning on at speed when you coast down a hill
Longer term im working on tapping into the ABS speed signal to disable the mod when you are at speed but im still testing this

My objective was to have no heat soak for the Snowy Mountains Race in and thsi was my last weekend to prepare

Results
No Heat soak!!!!

Cheers
34by151

 

Fantastic!

 

Good one.

I bought a couple of yours this board, not to control water sprays, but to control my engine fans:
AutoSpeed - Intelligent Intercooler Water Spray - Part 5

Never got to install it though, maybe one day...

They don't sell this board anymore, but maybe someone else has something similar to offer. I like it that you can control the fans based on a delta temperature (so x degrees above ambient), so it will only turn on if needed.

 

Avos, check this out for the delta temp
Ordering / Contact - myDTC Differential Temp Controllers and Outdoor Reset Control Store

Also here is a good article on AutoSpeed re the voltage controller
AutoSpeed - Triggering an Intercooler Fan

I also have a 10in fan to go in front, not sure if im going to use it yet

Cheers
34by151

 

Good find!

These differential ones are the ones I like best, as I prefer the fans to only turn on when needed, ie when the intercooler temps are for instance 10 or 15 degrees above ambient (regardless of speed).

I believe the stock fans are strong enough, at least for my car model.

 

I agree with you and this was my first thought, thats why I had the link for you

You also need to stop the fan at speed. There is no point above 80Kph and its possible to slow the airflow as well when at speeds above 80kph.

I'm working on a better solution to do that and more but as I indicated im only doing what I need to to get ready for the Snowy Mountains 1000. All other items are on hold till then

Cheers
34by151

 

Good work James, could be handy for us drag racers too
Although I'm thinking a manual switch would be enough and turn em off during pre-staging.

 

More to come on auto control I'm sure you will like, right up the drag race alley

The quick and dirty off the fog lamp is just a way of doing what you want without running wires into the cabin

Ive already run a 12core shielded cable from the engine bay to behind the dash, pleanty of spares for more stuff!!!

Did the same from the boot, at the time only needeed a few wires but its now there is only a few spare!!!

Cheers
34by151

 

Wow, this is almost identical to my research, I had almost exact same findings and also cut the control wire to the fan, now I had planned and actually installed a temp sensor in the return hose from the heat exchangers but found it to be relatively cool as compared to top of intercoolers, and hence would not turn on the fan.
I am now looking for a relatively low (like 160F) switch to install right at the coolers, I have also separated the charge cooler from the engine cooling system, and at current just have the wire accessible in the engine compartment for testing which reveals the car to run quite a bit stronger w. the fan going after idling, at speed the fan makes no diff.
On a side note disconnecting the fan control wire does set a fault code but not a ck engine light.