Ultimate Cooling System

[Woznaldo]

The temp in Sydney for the last week has been around 40 deg C with high humidity (80-90%) and the cooling system is struggling to keep it contained.

Most of my cooling system is new with the radiator being brand new OE just before I came over 5 years ago. The car was only road legal registered as of May last year. I'm not losing any fluid and the system works fine in the low 30's.

I'm going to look at something else, maybe even custom? I seem to remember Andrew Cooke mentioning a Honda Civic performance radiator. Has anyone tried one of these on a C1J GTT?

Has anyone got any other options? Is it worth getting an Oil Cooler to free up some cooling capacity of the OE Radiator?

If I'm going to do it right I should look at a FMIC at the same time to get the best cooling package.

Input welcome. :)

[i l k e r]

hi Woz,

the weather is roughly the same here in Cyprus and I never seem to have any problems cooling wise.

The only changes I made to the cooling system are that I run a seperate oil cooler and have a rad fan from a clio williams(not sure if it's better than the gtt one as I never had a o.e rad fan).

hope this helps mate :agree:

[Sparkie]

why not try using a 'water wetter' like the one redline make, to enable the transfer of heat from the water to the radiator..... - its basically a frothless detergent, to reduce the surface tension of the water.

[Matt Cole]

Woz, check your ethelyne glycol solution / mix. Too heavy on the antifreeze(not that you need it) reduces the heat transfer properties of the water.

[Os8472]

I use a R5 diesel rad, its bigger than a standard rad and doesn't hace the oil cooler so you'll need a seperat one.

Even with a split water pipe while on boost she didn't overheat, abit warm but it was a good 2 mins before I noticed the temp was up, normally she runs too cold for day to day motoring, hope this helps

[TNT ANDY]

I use a R5 diesel rad, its bigger than a standard rad and doesn't hace the oil cooler so you'll need a seperat one.

Even with a split water pipe while on boost she didn't overheat, abit warm but it was a good 2 mins before I noticed the temp was up, normally she runs too cold for day to day motoring, hope this helps

Oli - technically you could have a radiator the size of Uganda and the engine should run at whatever the stat is set at., so it shouldn't run cool on day to day running. If it does - up the temp of that stat if you can or set the fan kick in temp higher.

[Shane P]

Oli - technically you could have a radiator the size of Uganda and the engine should run at whatever the stat is set at., so it shouldn't run cool on day to day running. If it does - up the temp of that stat if you can or set the fan kick in temp higher.

This is what i have found as well (on a stock radiator), using a stat and fan switch which are 10-15 degress lower then stock keeps the temp between 40-55% of the way up the gauge regardless of how it is driven or outside temperature.

[Dave Reed]

Maybe drill a little hole in the top of the stat to. Move the oil out of the rad and see if that helps... If not source a bigger rad.

[Brigsy]

Flush the rad out with a hosepipe if it hasnt been done for a while & renewing the coolant will probably make a difference. Have you got the plastic cowling fitted around the rad??

Also what stat have you got fitted? 83deg never give me any problems in france even at silly speeds..a lot of the motorfactor stats are 86deg.

[sieger]

86 stat + oil cooler and a Fiat Uno Superdiesel rad.

works great:agree:

[Woznaldo]

I fitted a new water pump mid last year and did the full hose pipe flush thing. I even put some dishwasher powder (crushed tablet) through.

I think I might go for an oil cooler and try the water wetter solution and go from there. Thanks for everyones advice. :agree:

[danielmk323]

i m using a peg petrol rad is wilder oil cooler 14 row and bind the ren fan and using a fiat uno fire one i fond it it sucks more air then the ren one temp on stand still in the garage facing the wall don t go more then 75 and here is hot to and whit some more work i can fit some 8inc fan to on the front and use it whit a in car switch

[Matt Cole]

I fitted a new water pump mid last year and did the full hose pipe flush thing. I even put some dishwasher powder (crushed tablet) through.

I think I might go for an oil cooler and try the water wetter solution and go from there. Thanks for everyones advice. :agree:

Woz, are you using glycol? Reason i ask is if your just using water then corrosion will be inevitable and blocking the radiator.

[5teve L]

When you say struggling to keep it contained, do you mean it's boiling up ??
If so maybe a new header tank cap is needed ?

[Woznaldo]

I've managed to get hold of a coolant additive from Motul called MoCool. I'll see if it makes a difference over the next week. Here's a link:

http://www.motul.com.au/product_line_up/fork_brake_others/others21.html

[Mart]

Maybe drill a little hole in the top of the stat to

^ :agree:

If that doesn't work, a remote oil cooler will do the trick.

What coolant temperatures are you actually seeing though?

[Woznaldo]

I've already done the hole in the thermostat and it was working well. It's just the recent high temps that have been a struggle.

I don't know the temperature as I can inly go off the gauge but, during light cruising at 40-60 mph the needle sits right in the middle.

If I lose forward speed, and hence airflow, the temp will start to creep up to the top of the middle third which then triggers the rad fan to kick in, which in turn cools the temp down to 2/3 of the middle third.

If I start to get on boost for sustained periods, like on the motorway during some spirited overtaking up hill the temp will again creep up to the top of the middle third and maybe a little further. When the ambient temp was 40+ deg C doing the same motorway work, the temp could only be brought back into the middle third with the use of the heater on full whack!

I have yet to test the car in 40+ deg C temps since adding the MoCool as the weather has cooled recently (thank the freakin lord).

[Os8472]

Oli - technically you could have a radiator the size of Uganda and the engine should run at whatever the stat is set at., so it shouldn't run cool on day to day running. If it does - up the temp of that stat if you can or set the fan kick in temp higher.

I have the 89degree stat in mine, will sit fine till u give it a little squirt and the temp will drop and if i hammer it, it'll get very cold, derv rad + oil cooler + efi = damn thats cold

[Mart]

Woz, that sounds perfectly fine to me.

As long as the needle isn't going into the dashed 12 o' clock area, all is good.

Don't forget, the gauges are at best 20 years old, and I doubt they were calibrated (read needle position) that accurately in the factory.

[Adey aka Ewok]

I refitted the cowling on my 5s and it made a decent difference, well according to the oe gauge

[Woznaldo]

Woz, that sounds perfectly fine to me.

As long as the needle isn't going into the dashed 12 o' clock area, all is good.

Don't forget, the gauges are at best 20 years old, and I doubt they were calibrated (read needle position) that accurately in the factory.

Thanks Mart, like I've said, the temps have cooled off now so the problem hasn't arisen again but, as soon as I get another hot day, I'll go for a spin and report back.


I refitted the cowling on my 5s and it made a decent difference, well according to the oe gauge

I dont have any of the ducting fitted to my car. Maybe I'll knock up something with some aluminium sheet from work?

[Mart]

I dont have any of the ducting fitted to my car. Maybe I'll knock up something with some aluminium sheet from work?

It'll definitely make a difference :agree:

Likewise, for having ducting to route/force air through the intercooler as well.

[Woznaldo]

It'll definitely make a difference :agree:

Likewise, for having ducting to route/force air through the intercooler as well.

Intercooler is std OE at the moment but I want to go for a FMIC but, again I'm worried that this will block some of the airflow getting to the radiator and heat things up again?

[Alex]

I'm having similar problems at the moment. I've fitted a FMIC and therefore removed the radiator cowling. Under normal road driving conditions all is well (the temp is higher than before but it's not overheating) but when I'm on track after about 3 laps I'm having cool things down......

I'm going to make some cowling/duckting out of aluminium plates and see if that cures it. :)

[Brigsy]

I had the same problem on the van Alex, my cooler is 3" core so blocking a fair bit of the rad. Extra van 1.6 derv rad with external oil cooler has sorted it.

[Os8472]

for those with fmic a little detail i found out from an old rally chap, if your fmic sits infront of your rad, get them to sit as close to each other as possible so the air that passes through the fmic will go flow straight into the rad, if there is a big gap the air flow will become distorted and reduce cooling

[James5]

for those with fmic a little detail i found out from an old rally chap, if your fmic sits infront of your rad, get them to sit as close to each other as possible so the air that passes through the fmic will go flow straight into the rad, if there is a big gap the air flow will become distorted and reduce cooling

Would heat soak not be a problem if you had it to close? I run my grill mount intercooler with about a 10mm-15mm gap between them giving some clearance so no rubbage but also so I don't suffer with major heat soak, I know what your saying about air flow and on mine I run guards along the sides and top edge to stop any air flow from missing the rad but to help it go through the rad core, my temps are always good even after whatever abuse I give the 5.

[Mart]

for those with fmic a little detail i found out from an old rally chap, if your fmic sits infront of your rad, get them to sit as close to each other as possible so the air that passes through the fmic will go flow straight into the rad, if there is a big gap the air flow will become distorted and reduce cooling

Seems to work fine with a gap on Evo's, and their rally car variants...