Alloy radiators from Caterham

[Tony Martyr]

Has anyone any running experience they could share concerning the alloy radiators advertised by Caterham? Stupid name 'radiator' since they are heat exchangers that rely mainly on convention and conduction however black copper is better at the job than aluminium so an alloy unit has to have more surface area. Are they more efficient or lighter or both?

[Mike Bees]

The ali rad. does a better job of cooling IME. It is also lighter, but only when it's empty!

 

Mike

[Robbie J]

Go for it.

 

I had one fitted and the only thing you might be wary of it, is that on coller evenings it will run a fair bit cooler than the normal operating temp. Woth keeping an eye on the oil temp when that happens as that runs cooler obviously as well. But if you are concerned about overheating it puts all those worries to rest!

[tgracing]

Since my rad was swapped at Wiscombe for an alloy one I haven't noticed much difference, but thrashing it at Brands on the track for 15 minutes it sure was overheating well.

 

Davebo

C7 CAR

[Geoff Johnson]

Any idea's on what Ali radiators cost?

 

Geoff

[tgracing]

Not sure, but the Demon Tweeks list price is about 300GBP incl VAT. I only got charged about 150-170GBP by Classic Carriage.

 

Davebo

C7 CAR

[old captain slow]

I bought one direct from Caterham. It was about £180 for the large capacity one as far as I can remember. It comes with a couple of wing nut thingy's in the vent and drain holes. You need to put proper plugs in instead as the wing nut things break. Caterham will supply, but probably need to be reminded.

[Richard Ince]

If you are going to get a new rad look at the new triple pass ones that Caterham have just started selling. Fitting one to my car reduced the on track running temps by 10 degrees and my bank balance by about £300!

[Alex Wong1697456877]

What's a triple pass radiator?

[Richard Ince]

The Superlight R series this year has been very close (Well done Rob) and has involved cars running in each other’s slipstream. This restricted the airflow and made the cars run hotter that desired. The standard aluminium radiator was a single pass in that the water entered at one end and exited the other end.

To cool the cars Caterham developed the new triple pass radiator. This is made in three sections. Water flows into one end, into the first third section, across the radiator and then into the next section. Across the radiator as above and then into the last section, across the radiator again and out. This holds the water in the radiator for longer and increases the cooling efficiency.

I believe these radiators are now standard fit onto R500’s.

 

PS Good to see you at the Brands Dinner Dance Alex.

 

[Nick]

Re Rob winning the series, a lot of the races were very close yet he obviously has the knack of leading at the only time it counts, which calls for clever as well as fast driving - give that man a cigar!

[Alex Wong1697456877]

I wasn't at the Brands Dinner Dance!

 

Bloody Oriental's eh? They all look the same! smile.gif

 

 

 

Alex Wong

alex.wong@lotus7club.co.uk

www.alexwong.net

Home : 44-(0)121-440 6972

Fax : 44-(0)121-440 4601

[Richard Ince]

Sorry, I was sure it was you. Must have been your twin brother!

 

PS You missed a great evening.

[pie_boy69]

Having a little experience with automotive radiators ( my family has run a repair/fabrication shop for 21 years) I am a little disturbed to here thjat caterham have decided to sell this triple pass rad at an extra 120 quid as all it is is two tank section size plates of ally welded in the tank, the core being no different baring in mind that they should be selling us things that do the job properly why pay so much extra for something that cost 2quid in production.

As far as the extra cooling goes they used to sell a four row copper and brass rad which whilst being heavier will cool a lot better than an ali one.

Just a thought.

 

Keith Pickering

superlight T7 KCP

[Peter Carmichael]

I have had a big ally radiator since May 1999.

 

The ally rad does a better job of staying in one piece. The original (copper)radiator fell apart at the Nurburgring, although I would be happy to be pointed in the right direction to get it repaired.

 

I am wary of believing empirical observations that people make about cooling systems because of the non-linear behaviour of thermostats and the like. Excessively cool radiator return water temperature is liable to lead to the thermostat *panting* which is a bad thing leading to a cycle of overheating and subsequent over-cooling.

 

I am going to be running an 82 degree thermostat with my new engine. The standard k-series is 88 degrees. With a temperature sensor siting in the water rail (head output) I would expect to see a temperature reading higher than 88degrees. On my Stack dash (hopefully more reliable sensors than the standard) I tend to see steady running coolant temperatures of ~83 degrees. I therefore suppose that my thermostat is almost closed, most of the time and is panting. In traffic, with the fan on, the system holds everything steady at ~90 degrees, which looks likely to be thermostatically controlled.

 

From all of this, I suspect that there is a surplus of cooling capability in the big ally radiator. I think the same is true with the standard radiator and probably the new slimline ally radiator too. From the change in thermostat I would hope to see that traffic temperature come down by ~6 degrees. I do not expect the normal steady state running temperature to be affected much, but I would hope that the thermostat behaviour will be more stable and for the sake of dropping the running temperature by a degree or so the thermostat will be within its operating range and will never close completely.

 

I will also cross check the Stack sensor readings against the Emerald ECU readings and I will probably use the Emerald output to switch on the radiator fan at a lower temperature than at present.