Lets Talk Radiators Because there is some BAD information out (just replaced mine)

[Nicholas R]

Since the beginning of the LS1 project, cooling was something I was worried about.

I started with the "3 core brass radiator" that is pretty common these days.

Pretty sure it's the same one mentioned in this document:
https://support.delorean.com/KB/a44/radiators.aspx

A popular upgrade in the past was a 3-row brass radiator with metal tanks.

This radiator DEFINITELY, only has 2 cores! See for yourself!

This is the same radiator I see on many other cars, and everyone calls it the "3 core brass." No idea why, unless there is some other 2 core brass radiator floating around.

Anyone have a picture of a 3 core brass that actually has 3 cores?

So to make things even more interesting, a month ago or so, I borrowed a never used, original radiator (plastic bottles and all) from Cliff S. To take to a radiator shop and see if they had anything with similar dimensions. Now I had always heard that the original DeLorean radiator was 2 core aluminum. As far as I could tell, this is NOT true. First, it was definitely brass/copper (even this: https://support.delorean.com/KB/a44/radiators.aspx says it was brass). But when I took it to the radiator shop, they pointed out first thing, that it definitely was NOT 2 core, but rather just one single core going across. I wish I had taken pictures but its true, just one core running across!

This makes me wonder about the new radiator that DMCH has.
http://store.delorean.com/p-6273-radiator.aspx

This site: https://support.delorean.com/KB/a44/radiators.aspx says its 2 core, but when I called DMCH a few weeks ago, they said it was made from the factory drawings with metal bottles on the side so I'm not sure exactly what it is. Can anyone that has this radiator that can shed some light on it?

I'm also curious why it's paint black if it's aluminum. Brass/copper I understand because it will oxidize if it's not coated. Still painting black causes any material to absorb more heat via radiation. Aluminum shouldn't have to be painted.

In the end, this is the radiator I installed today:

Ed Uding's radiator from DMC Europe (Netherlands). Took about a week to arrive and was barely more than DMCH (including shipping!) It's 2 core aluminum, unpainted so it absorbs less heat (especially from the condenser).

Here is my brass 2 core radiator next to the new 2 core aluminum.

Here are the stats of each.
Original:
Brass, 2 core, 1.25 total core thickness, 18 fins, painted black.

New:
Aluminum, 2 core, 1.875" total core thickness, 27 fins, uncoated with bottles polished for even less absorption, core is also about 2" wider left to right than original.

Preliminary tests are good. Pushing the engine hard with AC on MAX I dont even think I've hit 200F yet. Hoping tomorrow will be really hot out so I can test it more in Florida heat.

[jackb]

I never understood why it was painted black either.

[Chris Burns]

Are you using the stock fans?

[Nicholas R]

Are you using the stock fans?

No, currently I have Toby Peterson's fans installed.

Also I forgot to post the pic of the old and new radiator next to one another:

[DCUK Martin]

Copper is a far better thermal conductor than aluminium and matt black not only absorbs radiant heat more efficiently, it emits it better too and on balance, being the hottest device, will emit far more than it absorbs. Though in practice a "radiator" is losing far more heat energy by forced convection.

The original is indeed a single row, I have had both twin and triple row cores made, with the twin row being the same depth as oem.

[Nicholas R]

Copper is a far better thermal conductor than aluminium and matt black not only absorbs radiant heat more efficiently, it emits it better too and on balance, being the hottest device, will emit far more than it absorbs. Though in practice a "radiator" is losing far more heat energy by forced convection.

The original is indeed a single row, I have had both twin and triple row cores made, with the twin row being the same depth as oem.

Thank you! I dont understand why so much documentation calls the original a 2 core radiator. Do you happen to know the depth of the core section of the originals? I recall it being about 1" but I cannot remember for sure. Just might be nice to know.

[LEVY]

Nicholas,

First, I understand black will not absorb heat by radiation, it will only absorb heat from direct sunlight, in other words, if it is in the shade, it will not absorb more heat than any other color. Now, black will disipate more heat than any other color, specially on the shade.

If you need a special radiator, give me the specs, I have a friend who owns a radiator factory and is willing to make one for me.

LEVY

[FLUXING]

How can applying a coating of paint, regardless of color, be more efficient at radiating heat away from the metal than just leaving the metal bare? There is bound to be retention of heat by the coating that wouldn't be there if the metal was unpainted....

[TTait]

Its also worth pointing out that a brass/copper core can be repaired much easier than an aluminum one. The price of copper is through the roof however...

[dmc6960]

How can applying a coating of paint, regardless of color, be more efficient at radiating heat away from the metal than just leaving the metal bare? There is bound to be retention of heat by the coating that wouldn't be there if the metal was unpainted....

A discussion about this came up when I was talking about AC condensers a while back. After a TON of research I came to the conclusion that in an aluminum heat exchanger unpainted gives the best heat transfer. There were still some disagreements on that though but I'm content with my conclusion. Now in the instance of a brass/copper unit, if the paint is necessary to prevent corrosion, then there is no choice in the matter. One of the key things to know is that in the application of a forced-air heat exchanger, the convection works best with no extra medium (paint) between the two main heat exchange mediums (in this case, aluminum and air).