Technical Ultimate Cooling (for n/asp Cento's)

[Liam]

Right, my own Cinq is running hot these days and the summer has just highlighted it to me.

So the purpose of this thread is to basically work out how to get the best cooling from the standard parts or parts from other models which are still relatively cheap.

I personally think my radiator is to blame for ines constantly sitting at over 90c in traffic, without using the blowers on full warm I would be forever listening to the fan.

So, I plan on the following, new radiator, alloy large core affair (Gex feel free to add the details of where to get one please) different thermostat which opens earlier but not too early as too cold is also a bad thing. Aaron will be able to tell us more on the thermo side. One question I have is where is it on the Cinq's? Is it the left hand side of the rad?

To go with the new rad and thermo would be "Water Wetter" to compliment it all, I believe it ain't cheap so a few of us could club together and split it up.

Basically anyone with useful information to add can post, I hope the thread benefits not only me but others maybe in the same position.

Cheers

Liam

 

[arc]

A fan override switch would be handy as well.

 

[custard]

thermostat is on the right under the coils. to be honest on my NA cinq once i fitted the new rad(basic ebay one)plus a new thermostat and coolant it ran perfectly. after that the cooling fan never came on in the motorway and in town i would have to be sitting in traffic for a good while for it to come on.
the turbo has no mods for cooling(YET!)and even that doesnt get too hot.
a new rad is really all you will need especially if you mesh the bumper.

 

[HP]

When you're sitting in traffic, if the water temp gets over 90'c and doesn't want to come down even though the fan's kicking in and out, it's a fair sign that your oil's up to about the 100'c plus mark.

so, oil cooler

 

[Liam]

Good advice people, keep it coming.

Won't be meshing my bumper though, too chavvy soory.

Liam

 

[custard]

custard will be meshing his,chavy or not

also there are other options to meshing. for example you can buy plastic brake ducts that can be flushed to the bumper and used to funnel air to the rad at an increased velocity. one on the drivers side for the rad and one on the passengers side for an oil cooler if fitted. of oyu have an induction kit you could fit one with a double feed to pipe air to that as well

 

[TurboCinqy1250]

A thermofanswitch from .... a tempra i thought is from 83 to 87 degrees celcius instead of the cinq 88 to 93 and it works a hell lot better than before.

Just 1 to 1 bold on type.

Only when you switch off the engine right at the moment the fan goes on, it will run for a minute of 5 to 10. So you can wait untill the fan stops and then switch the engine off if you don't like the afterrun of the cooling fan.

A new radiator will help to sometimes (corrosian and things like that.)

 

[custard]

yeah but then your listening to the fan more which on the cinq can be noisy. handy for prevention but a healthy cooling system is better

 

[TurboCinqy1250]

Most cooling problems you will get when you are not driving so the importest thing you need is airflow through your radiator. And that's what a coolingfan does. When it not switch on early enough your cinq is gone boil

 

[Surrey Sporting]

A thermofanswitch from .... a tempra i thought is from 83 to 87 degrees celcius instead of the cinq 88 to 93 and it works a hell lot better than before.

Just 1 to 1 bold on type.

Good tip - I think I'll get this for my cinq.

 

[J333EVO]

I'll put a little input on this from what I have learned from running modified R5 GT Turbo's which are know to run hot as everything learned from them can be transfered with the same thought process. 5's cooling problems have been ironed out with years of experimentation be various tuners who know what they are doing. You have been able to buy off the shelf lower temp coolant and rad thermo's for years for these cars, and copper core rads, just last week a 350bhp 5 set an 11 sec 1/4 mile in italy where it beat a near 600bhp Civic by quite a margin and it was an everyday car on road tyres which goes to show that its not headline power but how its used that maters, but back on track.

I found on my Cinq (ok its a turbo) that it ran at about 90 all the time which I believe is too hot as I also run an integrale which runs at 70ish al the time and its cooling system is in perfect health and running as it should which is good if you have ever seen under the bonnet of one as its cramped to say the least.

I have experimented with a few things heres what I found. The original iron rad in my car looked past its best but to see if it was I ran the car with no thermostat and it barely registered on the temp gauge, even with very spirited driving cross country which sowed that the rad if given a chance could keep things cool, though this was probably to cool. I then headed off to halfords and went through every thermo they had to see which one I could pull apart to use the centre section into the Cinq housing as it can come apart adn as of yet I've not came across a ready made one with a lower temp opening. I went for a 82 or 84 can't remember now but I did do a thread on it but this is about 10degrees lower than the Cinq one and it made a huge differance as the temp gauge never went above about 70 which I think is ideal. What you have to remember is that the temp stamped on the thermo is when it will be fully open so the Cinq's I believe is to high as the rad really doesn't have a chance to cool as the coolant doesn't reach it untill its hot, yes a bypass switch can help but its effect is marginal as the coolant doesn't leave the engine untill it gets to a predetermined temp.

I then experimented with a slighlty dif appraoch cos not everyone is going to take apart 2 perfectly good thermo's and rebuild one as it tricky and time consuming, so I took a noraml Cinq thermo and drilled out the very small bypass valve which allows a small amount of coolant through the rad prior to the thermo fully opening, this seems to be pretty good also as even in the last few weeks while its been hot I rearly see 90 even in traffic and the car runs fine and there are no start up problems. I think something like this added to the low temp rad fan swicth should expell all risk of boiling over cos there is a small margin to about 120degrees till this happens.

Though before doing any of this first flush all the system and renew coolant every 2 years or 3-4 if using the Mobil advanced coolant/anti freeze that I do. Water Wetter helps, but only in good quality coolant its not a miracle worker. make sure the expansion tank cap is in good condition as its a pressurised system and water under pressure has a higher boiling point these can be bought in Fiat or Halfords etc for about £5 so no need to not replace it. Ensure all hose clips are tight and renew if any look dodgy, and make sure the system is bleed correctly as air locks cos overheating as well.

If rad looks past it replace it, although I found the new ally rad made no diff at all that my origianl 8 year iron one except it was much lighter, must be worth a tenth of a bhp that

If i can make a turbo Cinq running 0.8bar of boost sit at over 120mph and not go above 85 degrees then there is no reason that an N/A one should run hot.

And if all else fails run an oil cooler for extra piece of mind, if an 1984 MG Metro has one, or for more modern times a Pug 106 Rallye has one and they are N/A cars then don't think that they are the preserve of turbo cars. Or if you know of a local rad builder, there are lots out there get a copper core rad made like they do on 5 turbo's they cool much much better than ally or iron rads, as an aside they stopped using ally rads on 5's as they just weren't good enough.

Aaron

 

[GhostWKD]

some very good ideas and input there Aaron

will have to have a look at that bypass valve on thermostat when i get round to 1242 i think :chin:

 

[custard]

another way is to drill a small hole through the thermostat so that some coolant is always flowing through. i'll be doing this on the turbo

edit:think i misread the previous post and this is what has been done.i read it as fitting a by pass pipe

 

[Liam]

Good advice still coming through (Aaron took you long enough to get here you womaniser! LOL)

I will add that although the thread is entitled cooling for N/A Cinqs I always uprate parts to take the most punishment so maybe the Turbo route is the one I will take.

Righty oh! More questions now: -

1. Is there anything wrong will a car running all the time with a water temp of constant 70c?

2. Will a radiator builder use the ends of the donor rad to make up the Copper one?

Liam

 

[J333EVO]

Good advice still coming through (Aaron took you long enough to get here you womaniser! LOL)

I will add that although the thread is entitled cooling for N/A Cinqs I always uprate parts to take the most punishment so maybe the Turbo route is the one I will take.

Righty oh! More questions now: -

1. Is there anything wrong will a car running all the time with a water temp of constant 70c?

2. Will a radiator builder use the ends of the donor rad to make up the Copper one?

Liam

Womeniser, says he the romancer! LOL

My integrale sits at about 65-70 all the time with out missing a beat, and my 5 used to sit the same, my Cinq also seems to be fine, obviously too cold is not good, but 70ish should be fine.

When I got my first rad built for the 5 about 8 years ago they used the end caps and just recored it with a copper core, cost me about £60 and was amazing, as I said thats now the standard for 5's as the ally ones are prown to blocking up as ally rads use smaller water ways than the iron ones, I heard that BMW 3 E30 and E36 series used to have major over heating problems with there ally rads as well.

HTH Aaron.

 

[Liam]

End caps, thats the phrase I was looking for!

Hmm, I'll price one of these, are they copper in colour then i.e like water pipes? Sounds obvious and it's maybe a silly question but just wondering.

Have you ever priced a rad @ BMW? The quote a long number, you say is that the part number and they say no that's the price!

Liam

 

[J333EVO]

End caps, thats the phrase I was looking for!

Hmm, I'll price one of these, are they copper in colour then i.e like water pipes? Sounds obvious and it's maybe a silly question but just wondering.

Have you ever priced a rad @ BMW? The quote a long number, you say is that the part number and they say no that's the price!

Liam

What ever price B-em-dubya quote is probably massively bumper up as most rads in Europe are made by Valeo or Magneti Marelli but i do know of an after market rad and oil cooler combination for an integrale that retails at £1600! It should not be cooper in colour more lickly black as they paint it as black is a better condustor and all that but you can scratch the paint to reveil the copper underneath.

Aaron.

 

[custard]

had the turbo out tonight and sat cruising bout 75 on the motorway.temp settled at about 70/75 lthough a little right pedal action got it up to 90 degree terrirtory. guessing its either had most off the cooling components replaced and/or a drilled or removed thermostat as well

 

[J333EVO]

I can nail mine for a good few miles at speeds to make the eyes water and it doesn't go that high, especially on a cool night like tonight.

Aaron.

 

[Liam]

Ambient outside temp does have a factor in it, winter round my way the gauge rarely goes near 70c because the blowers are on plus outside it is cold.

Over the weekend it was overcast and sometimes wet and my Cinq never hit 90c, drove in the afternoon today, better day, open road bit of hammering, blowers set to cool and up goes the gauge! Pest!

I am searching for rads, now some say alloy allows more rows, would OE rads be a copper/iron mix painted black?

Liam