Anyone familiar with these aluminum radiators?

[tdskip]

I need to get planning on my radiator, was doing some searching and came across this on eBay.

[mbell]

Not directly but they post on this forum! Think people are generally happy with the product. Search "coolex" and you get decent amount of info.

[tdskip]

Not directly but they post on this forum! Think people are generally happy with the product. Search "coolex" and you get decent amount of info.

Thanks - will get that search going.

[nmauduit]

I have one on my street S4se, very satisfied customer (no affiliation)

they go by coolexperts on the forum

search.php?author_id=6712&sr=posts

[tdskip]

Thank you for the note, good to hear that you?ve had a good experience. I will get searching on this and follow up with any questions. Thank you!

[danielmo]

You may want to consider this radiator.

https://www.ebay.com/itm/2-ROW-CORE-FUL ... SwqYxc-8jZ

You'll have to have the top inlet cut and re-weld it at a different angle, but certainly not to the tune of $400.

[tdskip]

Thanks for posting that, I had not considered that as an option.

Taking a step back - I have access to the original radiator but it?s an unknown condition and is obviously old at this point. I?ve been working on the assumption that a new one would be close to the same cost of getting the old one refurbished and of course the new one would have the advantage of being operated and it?s cooling capacity. Is that the right way to think about it if I?m not stuck on originality?

Thanks!

[crypto]

You may want to consider this radiator.

https://www.ebay.com/itm/2-ROW-CORE-FUL ... SwqYxc-8jZ
....

I'm also looking for an alloy rad, but it seems really hard to compare the alloy ones of different manufacturers with the original copper/brass type ! Most manufacturers give only brief descriptions of the core and dimensions and make useless claims like "improved version of original ..." or "used in racing ...", but NO real technical data to compare the cooling efficiency of a specific radiator.

I agree such performance data are not easy to obtain and requires a good understanding of physics and calculations, apart of being a good alloy welder.

The tubes in my current copper rad look like this (seems to be a genuine S4/Sprint rad, maybe someone can confirm ?)

On closer look they are arranged like this on the left:

If you order an alloy rad that has the same dimensions, the same tube sizes and spacing and same number of fins you will get a much worse radiator than the old copper one. This is because thermal conductivity of copper is 80% higher/better versus aluminium.

Why go for an alloy rad then ? There are physical and manufacturing reasons:
a) a good alloy rad has wider tubes compared to a copper one (due to strength of alloy), so there are fewer rows as in the right pic
b) due to higher strength it also allows closer tube spacing and a higher stacking ratio of about 4:3, increasing the number of fins significantly

To additionally improve cooling the tubes should run in the longest radiator dimension

Unfortunately there are a lot of cheap (Chinese ?) rubbish radiator cores around. I would ask the seller about the tube dimension/spacing, so you know what you (not) get.

To find out if my cooling system is good enough, I drive one or two passes in the alps on hot summer day. Driving one hour upwards with a lot of acceleration and much less airflow than a race stresses the cooling (and engine) to limit.

[nmauduit]

To add a bit to my previous comment: the stock, wide copper radiator of my S4 was colling very satisfactorily the stock engine. One summer track day I started to get oevrflowing radiator, and decided to add lightness with a aluminium one, but it turned out it was a head gasket that was starting leaking. I also added electrical blow through fans to the new radiator (more efficient than the stock one), as I have sealed up the bay with the foam and since under bonnet heat can rise quite a bit when stoping after a run.

Copper conducts heat better than aluminium (provided a good coolant is used and it is not gummed with green oxide or scale), but I think aluminium radiates better, so if one if after the best of both world copper tubes with aluminium cooling fins could be used...

[William2]

I have used this company and fitted one of their rads. Very well made and nice folks to deal with.

[Andy8421]

To add a bit to my previous comment: the stock, wide copper radiator of my S4 was colling very satisfactorily the stock engine. One summer track day I started to get oevrflowing radiator, and decided to add lightness with a aluminium one, but it turned out it was a head gasket that was starting leaking. I also added electrical blow through fans to the new radiator (more efficient than the stock one), as I have sealed up the bay with the foam and since under bonnet heat can rise quite a bit when stoping after a run.

Copper conducts heat better than aluminium (provided a good coolant is used and it is not gummed with green oxide or scale), but I think aluminium radiates better, so if one if after the best of both world copper tubes with aluminium cooling fins could be used...

Car radiators are not 'radiators' in a technical sense that they radiate heat as their main heat dissipation mechanism, but are heat exchangers between two fluids - water and air. Although copper is a better conductor than aluminium by volume, aluminium is a better conductor than copper by weight, and effectiveness of a heat exchanger is a function of surface area. All other things being equal, an aluminium rad with the same ability to dissipate heat as a copper rad would be lighter, or alternatively if the two rads weighed the same, the aluminum rad would be able to dissipate more heat. It is more complicated than that - in a size limited application like the Elan, for an aluminium radiator to work as effectively as a copper radiator it would need more fins and possibly tubes, but could still turn out to be lighter and probably cheaper.

[snowyelan]

Just to add to this, I bought one of the Ebay triumph rads linked above. NOT THE COOLEX RAD. Cheap, but you get what you pay for. Its discounted for a reason. The top tank has been cut and a new section welded in. Best guess is something wasn't right the first time round. Not worth the hassle of sending back and I'll probably see if I can make it work. Plan is to push it into the nose further. One other thing, its painted silver. Probably a cheaper process than polishing it. You get what you pay for....

[jbeach]

I have the Coolex aluminum with two Revotec fans mounted on engine-side of radiator. I couldn?t be happier. So far, bulletproof.
-John