Cooling Project

[newthings]

I haven't been burned and don't want to be, by being out on a 100+ day, crawling along with little air moving over the radiator and integral transmission cooler. I have seen the temp gauge move toward the high side in moderate conditions and wonder how much cooling headspace I have. High temps challenge lubricants and seals. Less is better.

Talking with the Alpine guys a while back, they said a radiator with more tube rows is not good, since the air friction through the thicker core of fins slows down the heat transfer process and is less efficient than a thin stock core. A three tube core has more surface area and liquid capacity, but poorer transfer. Some gain, but not the best bang for the buck. They indicated the removal of the transmission heat load with an external cooler is the best idea.

If removing the oil cooling load from the stock radiator is good, how about having the whole radiator area devoted to engine cooling - as in a new radiator with no trans cooling built in? Aluminum or copper? I like copper and brass for solder reparability and less fragility. (Ours is plastic and aluminum) OK, but where to put the oil cooler with fan?

I toyed with the idea of using that across the hood bug deflector as a model for housing a narrow oil radiator. I also thought about using an extruded aluminum finned heat sink plate with oil passages, filling the hood insert area with the fins in the wind. Both of these ideas would look pretty dramatic. Maybe later.

I have a Calmini air filter and with no stock airbox, I have some room for a cooler. The old intake hole in he fender could be used to exit hot air. Hmm.

So off I went with my ideas to the radiator shop and became convinced the best thing was to go for the stock thickness radiator in copper with the stock electric fan on the passenger half of the radiator and to add an oil cooler with fan on the driver side of the radiator. The A/C condenser is in the stock position and the clutch fan is kept. I never liked the idea of hose clamps on the oil lines so I am going for an AN type flair fittings to the oil cooler.

This may end up costing about $800. Equal amounts for parts and labor. As in most mods, much is learned from the prototype. I have asked the shop to consider what a kit might look like, since others might have an interest

Any comments or ideas before I commit?

Roy

[Dallas4u]

Sounds like a worthy idea! I didn't even think about the radiator being a tranny cooler as well. Hmm... I may have to do some rethinking on this subject.

I would think about placing a seperate tranny cooler (and maybe an engine oil cooler) somewhere outside of the engine compartment, maybe under the car if possible, out of the way from getting punctured or course.

[Triathlete]

I've been off-roading going under 10 MPH for 6+ hours in 100+ degree heat with the windows up and air conditioner on high and have never seen my temp gauge go above mid way! ;Dr; ;eekr; ;Dr; ;eekr;

[Green Dragon]

Originally posted by Triathlete
I've been off-roading going under 10 MPH for 6+ hours in 100+ degree heat with the windows up and air conditioner on high and have never seen my temp gauge go above mid way! ;Dr; ;eekr; ;Dr; ;eekr;

I would be taking a hard look at the that temperature gauge. I have done my share of long hard wheeling and have learned to
keep the air off whenever possible (exception is extreme dust)as the temp goes from just left of center to almost max rt when stopped for delays without shutting down

[Navigator]

A bottle of Water Wetter in the radiator helps.

[dtruax]

Originally posted by Triathlete
I've been off-roading going under 10 MPH for 6+ hours in 100+ degree heat with the windows up and air conditioner on high and have never seen my temp gauge go above mid way! ;Dr; ;eekr; ;Dr; ;eekr;

Same Here - I drive in 100 - 110 degree at a craw for hours in 4x4 Poker runs, etc with the A/C on. I was starting to get worried, because my gauge never goes over 1/2.

[Spike]

I agree, That neon pink stuff seems to work very well.

[MrCrowley]

i havent had any temp problems, and especially after I moved to Alabama. its Mid June, and we havent even seen 90 yet! You guys can keep the heat. If anyone does a radiator swap. ALUMINUM ONLY. Copper is outdated. aluminum dissipates heat much better than anything other than exotic metals. Some companies make 100% aluminum radiators too. I think Be Cool is one. There are also a few companies that make coolers with two fluids. ie tranny and oil. There are also spin on plates for where the oil filter goes for an in and out, and then your filter spins on its bottom like normal. Now let me see if I can get that GM crap radiator out of my Isuzu...

[newthings]

Aluminum better than Copper Radiators ???
Except for weight, it’s not exactly so with modern copper construction.
(Weight is what lets me pull some big dog out of a pond with my "Little Car")
Here is some analysis from various internet sites –

In determining the appropriate metal for car and truck radiators, an important criterion in recent years has been relative weight. Because of its low density, aluminum has grown in popularity for this purpose despite its inherent weaknesses in thermal conductivity, corrosion resistance and repairability.

Particularly impressive is the fact that a copper/brass radiator core is far more energy efficient than an aluminum radiator core of equal weight (336 KWh vs.426 kWh).

When you combine copper/brass's superior thermal conductivity, corrosion resistance and strength with it's highly favorable life-cycle energy use, virtual 100% recyclability, and exceptionally low energy cost as remanufactured scrap, it becomes clear that the world's oldest known metal will be even better for tomorrow's car and truck radiators.

And this –
The recent history of the passenger car radiator is well known - the conventional wisdom is that aluminum has largely taken this market. The trend started in Western Europe, has moved forward in the United States and has more recently taken hold with Japanese automobile producers. But aluminum penetration in the large aftermarket is only about 10%

But the copper/brass radiator was too heavy - not because the laws of physics dictated that it be, but because no effort to improve design to take advantage of superior mechanical properties and thermal conductivity had been expended. More recently, in tests conducted at Penn State University on three generations of the new brazed copper/brass radiator, CuproBraze radiators were shown to be fully competitive with the brazed aluminum.
These data are shown in the table below.
Table 4.
CuproBraze vs. Brazed Aluminum
Radiator Core: Brazed Aluminum CuproBraze I* CuproBraze II* CuproBraze III*
CoolantPressure Drop, kPa
4.75 3.31 2.89 4.75
Air Pressure Drop, kPa
0.307 0.216 0.307 0.307

CuproBrazeI, designed to have the same frontal area as the aluminum radiator, has 30% lower air pressure drop but is slightly heavier.
CuproBrazeII has the same air pressure as the brazed aluminum model, but is smaller in size.
CuproBrazeIII combines a smaller frontal area and thinner tube walls to achieve distinct advantages in both size and weight.
All four of these radiator cores have the same cooling capacity (168,000 BTU/hr) and fin depth. Their weights include fin and tube material only. This work has shown conclusively that a much lighter copper/brass radiator is possible. In addition to replacing the lead solder by a brazed joining system, tube touching design and compact core designs were among a number of innovations that reduced the weight of the copper/brass system.

And this from the Sunbeam Tiger page–
Aluminum conducts heat about 1/3 better than brass. However, copper conducts heat about twice as good as aluminum. Then again, the brass/copper is held together with solder which conducts heat poorly at a rate about 1/5 as good as aluminum. If aluminum radiators had to use the same design dimensions as brass/copper radiators, aluminum radiators would be less efficient than brass/copper radiators.
NEW DESIGNS USE LEADLESS BRAZING.

From chevyhighperformance.com –
Many new performance radiators, such as those
from Griffin and Be Cool, are made from
aluminum that offers weight savings over
copper-brass. While aluminum does not
dissipate heat as well as copper-brass, modern
radiator design more than makes up for the
difference

Look here for a test. –
http://www.usradiator.com/testing.htm

Roy