Brass or Aluminum Rad. Which is best?

1971 Dart Swinger. 318, 2-bbl (soon a 4-bbl), auto, PS, A/C with 115000 miles. Original radiator. Just a cruiser.

Would you replace with a Brass or Aluminum radiator?

Stock replacement is more than adequate

The only thing you get with an aluminum radiator is weight savings, cooling is actually better with an OEM style. But, you can usually find the aluminum radiators cheaper.

That's a fact...

OEM was out there in millions of vehicles...

And worked just fine...

Agreed & for your app an alum will be fine. I used a Champion ($189 to my door/eBay) in a 65 dart with an 83 318 & it was perfect tho a 318 sure ain't gonna test its cooling capabilities. it was a 2 row and there's been talk that the coolant tubes are smaller but for your app it'd be a non issue. I only had to redrill (1) mounting hole in the Dr side flat flange. If you get one check that it is flat & all welds are good/complete tho those reported probs are somewhat scarce & reportedly have been addressed. The alum does look horrid & you'd wanna paint it. You will save hundreds going with alum

Comparing the exact same size to size the copper and brass will cool better I've had issue with aluminum radaitors cooling good for the first year and then run hotter the next year with no changes I had to have that radaitor back flush every year to keep the motor running under 200 F

Either should work fine. The main drawback to aluminum is they are generally a universal fit that may or may not accommodate the factory shroud, mounting holes etc. Rock auto has a couple of stock replacements listed for just under 200.00. A bit of shopping may better those prices ?

Electrolysis???

A heat exchanger usually loses efficiency by fouling. Even a very thin layer of something in the tubes can cut the total heat transfer rate by quite a bit.

You will not save hundreds going with aluminum.

Cheapest radiator at Summit racing for this application is brass, $227.97.

Next cheapest is a cross flow aluminum universal, $323.97.

http://www.summitracing.com/search/year/1971/make/dodge/model/dart/department/cooling-heating/section/radiators/part-type/radiators?N=4294950315%2B4294951331%2B4294947955%2B4294950709%2B4294949676%2B4294949245&SortBy=DisplayPrice&SortOrder=Ascending

You can get the direct fit OEM type at Rock Auto for a bit less than Summit, about $200. In order to "save hundreds" your aluminum radiator would have to be free, shipped free and install itself without mods, which the cheapest AL direct fit (aka no mods needed) is over $600 at Summit.

You might find a universal (fits nothing) AL radiator on E bay that can be made to work, most likely without the factory shroud fitting easily, for maybe $15 less, not counting shipping differences or mods needed.

Assuming you even need a radiator at all, is this a proactive replacement or do you need a radiator

Agreed...

Just wondering if coolant passing between a cast iron block, and an aluminum rad has a negative effect on the core...


I've got an OEM copper/brass rad that I've been running for over 20 years...

Appears to be little, or no 'fouling' in the transfer tubes looking in from the filler neck...


Still cooling just fine...

On this subject about the radiators and not to take away from the OP, here is my question: Seems the census says that original or brass radiators will be ok. Will the same be said for a big block engine, making big HP, and with A/C?

Thanks

The OP will be fine with an orginial type replacement. I run a universal aluminum two tube crossflow aluminum on my Dart. My 408 was in the 550 hp range and never ran over 180 in hot weather. I suspect it will cool my new 434 without any issues. I did have to fab up the mounting brackets and a shroud, certainly not rocket science. Factory replacement hoses fit it too, $175 from a local roundy round shop.

Talked with a tech at a local rad shop. They do rads for customs in the area. Their advice to beat the Arizona hot temps is an OE with a minimum of three rows, 180 T-stat and a good water pump. They said to stay away from aluminum unless racing.

I've replaced a number of "cheap" aluminum radiators in big block & small block MOPARs that had overheating "issues" out here in the VEGAS heat with stock OE style brass/copper radiators with positive results.

The recent overload/marketing of cheap aluminum radiators and the perception that they are an improvement over OE style because big money motorsports like NASCAR teams use them is a problem. NASCAR uses aluminum radiators - "it must be the solution to my overheating problems" - did you ever see the size/volume of a NASCAR radiator? I can only imagine the cost.

Aluminum is CHEAP, off-shore manufacturing is CHEAP, lets market a cost competitive (based on not well understood cooling properties with bigger profit margins than brass/copper) solution to everyone's perceived high cost cooling needs. Yeah, that'$ the ticket!!

That and with most they use epoxy to seal the seams

I too am considering a new radiator (as a preventative measure) and have some of the same concerns as the OP (nearly identical vehicle as well).

Is there any special maintenance that must be done with an Aluminum vs. Copper/Brass radiator?

FABO member challengergary suggested Champion Radiator (CC526) is a bolt in for $235 to my door.

Any opinions?

This seems like a topic that comes up often! One thing to watch is the specifications, including and especially the lower cost brass/copper replacements. I had this problem on a '78 PU. 3 core "extra cooling" parts store copper/brass radiator and she would warm up on a hard pull in hot weather. On a roll. Those rows were thin.

The other is cost. A factory style radiator built or re-cored with a 3 or 4 row high efficiency brass core should cool great. Also not cheap. Same comment on a higher end aluminum unit. They cool great but are not cheap.

The pickup (brand F) got a 4 core Champion. The stock shroud fit and it cools much better than the parts store brass unit.

My stroker BB with AC runs a higher end aluminum radiator (Mancini Muscle Car radiator). Stock mounting, stock hoses and made to order shroud. Cooled great for 10 years, including stop and go in Las Vegas, until a super single gator took it out. I got another.

For the OP, a 3 core Champion may do the trick if they make one for that application. A Mancini or Griffin radiator made to spec should work great. A high end copper/brass unit (Glen Ray I believe) would certainly do it. Personally, in that application, I would try the Champion. If you want to be really sure, the Glen Ray, Mancini or Griffin.

My 2001 V10 5-speed quad cab had the typical aluminum/plastic radiator and I had to replace it at 25K miles. It sat for a few years before I bought it and somehow rotted out the connection between the core and the plastic sides. I also had issues with the heater core because it sat so long without having the coolant flowing.

Brass is better and will last longer. If you use an aluminum radiator, you better buy one of these.

Given two radiators of identical design, an aluminum one would cool (transfer heat) better than brass, since the thermal conductivity of aluminum is better than brass.

I get asked this question so often that I feel like a broken record telling the pros & cons over and over. I am not a scientist, chemist or engineer but based on my 33 years in the radiator business here is my opinion on which is better; copper or aluminum radiators.

There is much debate over whether a copper or an aluminum radiator will cool better. There are pros and cons to each material. It has been scientifically proven that copper actually transfers heat better than aluminum. It is easier to repair in most cases than aluminum and until the last couple of years was much less expensive. The drawbacks to a copper radiator are the weight difference (aluminum is much lighter) and the solder joints that hold it together.

..... but you can't build an aluminum radiator to IDENTICAL spec's of a brass/copper radiator. The tubes of a vintage brass/copper radiator are ~0.007" thick (modern aluminum beer can) modern aluminum radiators are ~0.016".



from aluminum radiator info....

You sir are sadly mistaken on the conducitivity of aluminum and cooper and brass for heat and electricity

Arguing with scientifically proven facts??


BTW, electrical conductivity and thermal conductivity are two entirely different properties of materials.

Thermal conductivity for common materials and products:

Thermal Conductivity
- k -
W/(m K)
Material/Substance Temperature - oC
25 125 225
Acetals 0.23
Acetone 0.16
Acetylene (gas) 0.018
Acrylic 0.2
Air, atmosphere (gas) 0.024
Air, elevation 10000 m 0.020
Alcohol 0.17
Aluminum 205 215 250
Aluminum Brass 121
Aluminum Oxide 30
Ammonia (gas) 0.022
Antimony 18.5
Apple (85.6% moisture) 0.39
Argon (gas) 0.016
Asbestos-cement board 0.744
Asbestos-cement sheets 0.166
Asbestos-cement 2.07
Asbestos, loosely packed 0.15
Asbestos mill board 0.14
Asphalt 0.75
Balsa wood 0.048
Bitumen 0.17
Bitumen/felt layers 0.5
Beef, lean (78.9 % moisture) 0.43 - 0.48
Benzene 0.16
Beryllium 218
Bitumen 0.17
Blast furnace gas (gas) 0.02
Brass 109

Where is the balance of the list ? You need to go farther and include copper !!

Since you asked.....

Basically, the thermal conductivity of aluminum is about 2 times greater than brass and copper is about two times greater than aluminum.

Thermal conductivity for common materials and products:

Thermal Conductivity
- k -
W/(m K)
Material/Substance Temperature - oC
25 125 225
Acetals 0.23
Acetone 0.16
Acetylene (gas) 0.018
Acrylic 0.2
Air, atmosphere (gas) 0.024
Air, elevation 10000 m 0.020
Alcohol 0.17
Aluminum 205 215 250
Aluminum Brass 121
Aluminum Oxide 30
Ammonia (gas) 0.022
Antimony 18.5
Apple (85.6% moisture) 0.39
Argon (gas) 0.016
Asbestos-cement board 0.744
Asbestos-cement sheets 0.166
Asbestos-cement 2.07
Asbestos, loosely packed 0.15
Asbestos mill board 0.14
Asphalt 0.75
Balsa wood 0.048
Bitumen 0.17
Bitumen/felt layers 0.5
Beef, lean (78.9 % moisture) 0.43 - 0.48
Benzene 0.16
Beryllium 218
Bitumen 0.17
Blast furnace gas (gas) 0.02
Brass 109
Breeze block 0.10 - 0.20
Brick dense 1.31
Brick, insulating 0.15
Brickwork, common (Building Brick) 0.6 -1.0
Brickwork, dense 1.6
Bromine (gas) 0.004
Bronze 110
Butter (15% moisture content) 0.20
Cadmium 92
Calcium silicate 0.05
Carbon 1.7
Carbon dioxide (gas) 0.0146
Carbon monoxide 0.0232
Cellulose, cotton, wood pulp and regenerated 0.23
Cellulose acetate, molded, sheet

0.17 - 0.33
Cellulose nitrate, celluloid 0.12 - 0.21
Cement, portland 0.29
Cement, mortar 1.73
Chalk 0. 09
Charcoal 0.2
Chlorinated poly-ether 0.13
Chlorine (gas) 0.0081
Chrome Nickel Steel (18% Cr, 8 % Ni) 16.3
Chromium 94
Clay, dry to moist 0.15 - 1.8
Clay, saturated 0.6 - 2.5
Coal 0.2
Cobalt 69
Cod (83% moisture content) 0.54
Concrete, lightweight 0.1 - 0.3
Concrete, medium 0.4 - 0.7
Concrete, dense 1.0 - 1.8
Concrete, stone 1.7
Constantan 22
Copper 401 400 398
Corian (ceramic filled) 1.06
Cork board 0.043
Cork, re-granulated 0.044
Cork 0.07
Cotton 0.04
Cotton wool 0.029
Carbon Steel 54 51 47
Cotton Wool insulation 0.029
Diamond 1000
Diatomaceous earth (Sil-o-cel) 0.06
Diatomite 0.12
Earth, dry 1.5
Engine Oil 0.15
Ethane (gas) 0.018
Ether 0.14
Ethylene (gas) 0.017
Epoxy 0.35
Ethylene glycol 0.25
Feathers 0.034
Felt insulation 0.04
Fiberglass 0.04
Fiber insulating board 0.048
Fiber hardboard 0.2
Fire-clay brick 500oC 1.4
Fluorine (gas) 0.0254
Foam glass 0.045
Freon R-12 (gas) 0.007
Freon R-12 (liquid) 0.09
Gasoline 0.15
Glass 1.05
Glass, Pearls, dry 0.18
Glass, Pearls, saturated 0.76
Glass, window 0.96
Glass, wool Insulation 0.04
Glycerol 0.28
Gold 310 312 310
Granite 1.7 - 4.0
Gravel 0.7
Ground or soil, very moist area 1.4
Ground or soil, moist area 1.0
Ground or soil, dry area 0.5
Ground or soil, very dry area 0.33
Gypsum board 0.17
Hairfelt 0.05
Hardboard high density 0.15
Hardwoods (oak, maple..) 0.16
Helium (gas) 0.142
Honey (12.6% moisture content) 0.5
Hydrochloric acid (gas) 0.013
Hydrogen (gas) 0.168
Hydrogen sulfide (gas) 0.013
Ice (0oC, 32oF) 2.18
Insulation materials 0.035 - 0.16
Iridium 147
Iron 80 68 60
Iron, wrought 59
Iron, cast 55
Kapok insulation 0.034
Kerosene 0.15
Krypton (gas) 0.0088
Lead Pb 35
Leather, dry 0.14
Limestone 1.26 - 1.33
Magnesia insulation (85%) 0.07
Magnesite 4.15
Magnesium 156
Marble 2.08 - 2.94
Mercury, liquid 8.3
Methane (gas) 0.030
Methanol 0.21
Mica 0.71
Milk 0.53
Mineral wool insulation materials, wool blankets .. 0.04
Molybdenum 138
Monel 26
Neon (gas) 0.046
Neoprene 0.05
Nickel 91
Nitric oxide (gas) 0.0238
Nitrogen (gas) 0.024
Nitrous oxide (gas) 0.0151
Nylon 6, Nylon 6/6 0.25
Oil, machine lubricating SAE 50 0.15
Olive oil 0.17
Oxygen (gas) 0.024
Paper 0.05
Paraffin Wax 0.25
Perlite, atmospheric pressure 0.031
Perlite, vacuum 0.00137
Phenolic cast resins 0.15
Phenol-formaldehyde moulding compounds 0.13 - 0.25
Plaster light 0.2
Plaster, metal lath 0.47
Plaster, sand 0.71
Plaster, wood lath 0.28
Plasticine 0.65 - 0.8
Plastics, foamed (insulation materials) 0.03
Platinum 70 71 72
Plutonium 6.7
Plywood 0.13
Polycarbonate 0.19
Polyester 0.05
Polyethylene low density, PEL 0.33
Polyethylene high density, PEH 0.42 - 0.51
Polyisoprene natural rubber 0.13
Polyisoprene hard rubber 0.16
Polymethylmethacrylate 0.17 - 0.25
Polypropylene, PP 0.1 - 0.22
Polystyrene, expanded styrofoam 0.03
Polystyrol 0.043
Polyurethane foam 0.03
Porcelain 1.5
Potato, raw flesh 0.55
Propane (gas) 0.015
Polytetrafluoroethylene, Teflon, PTFE 0.25
Polyvinylchloride, PVC 0.19
Pyrex glass 1.005
Quartz mineral 3
Radon (gas) 0.0033
Rock, solid 2 - 7
Rock, porous volcanic (Tuff) 0.5 - 2.5
Rock Wool insulation 0.045
Rubber, cellular 0.045
Rubber, natural 0.13
Salmon (73% moisture content) 0.50
Sand, dry 0.15 - 0.25
Sand, moist 0.25 - 2
Sand, saturated 2 - 4
Sandstone 1.7
Sawdust 0.08
Sheep wool 0.039
Silica aerogel 0.02
Silicone cast resin 0.15 - 0.32
Silicone oil 0.1
Silver 429
Slag wool 0.042
Slate 2.01
Snow (temp < 0oC) 0.05 - 0.25
Sodium 135 (solid) 86 (liquid)
Softwoods (fir, pine ..) 0.12
Soil, clay 1.1
Soil, with organic matter 0.15 - 2
Soil, saturated 0.6 - 4
Steam, saturated

0.0184
Steam, low pressure 0.0188
Steel, Carbon 1% 43
Stainless Steel 16 17 19
Straw slab insulation, compressed 0.09
Styrofoam 0.033
Sulfur dioxide (gas) 0.0086
Sugars 0.087 - 0.22
Teflon 0.25
Timber 0.14
Tin Sn 67
Titanium 22
Tungsten 174
Uranium 27.6
Urethane foam 0.021
Vacuum 0
Vermiculite granules 0.065
Vinyl ester 0.25
Water 0.58
Water, vapor (steam) 0.016
Wheat flour 0.45
Wood across the grain, white pine 0.12
Wood across the grain, balsa 0.055
Wood across the grain, yellow pine, timber 0.147
Wood, oak 0.17
Wool, felt 0.07
Wood wool, slab 0.1 - 0.15
Xenon (gas) 0.0051
Zinc Zn 116

Wow, someone figured out how to cut and paste an entire page from wikipedia.

So what. The OEM's didn't go to aluminum cause it's better at transferring heat, they went cause it's lighter.

What's the thermal conductivity of WATER, cause that is your limiting factor NOT aluminum or brass. But leave it to a textbook engineer to miss the salient point of a SYSTEM.

And why is an aluminum radiator more costly when at current metal prices,aluminum is $0.70 lb,brass $1.34 lb and copper at $2.12 lb ?

Yes, there are many factors that need to be considered in product design. The performance of the material, the strength of the material, the cost to form the material, and the cost to manufacture the product. In this case, aluminum not only transfers heat better than brass, it's cheaper. And yes, an aluminum radiator will be designed differently than a brass radiator, so the total amount of material used, will be different.

And supercuda....the water and coolant used will be the same in both a brass or aluminum radiator so that's not even relevant for comparison purposes.

Your whole supposition is that aluminum is better than brass because it has sslightly better thermal conductivity, the difference in thermal conductivity between water and/or brass and aluminum is orders of magnitude, the restrain on the transfer is the water's ability, not the brass or aluminum's.

It's like arguing that 5/8" fuel line is better than 1/2" because it flows more, into a BBS carb. Irrelevant.

Tale of two cars, father-sons. Sons, 528 all aluminum Hemi with big aluminum radiator, runs over 2 hundred or more, all the time, with two fans and custom made shroud. Fathers, 472 Hemi steel block aluminum heads stock radiator no shroud, like it came off the line, runs 160 all day, any temp outside. 63&65 Dodges. I told him to get rid of the rad. and electric pump, won't listen, steady throwing money at it??

Tale of two different cars, apples to oranges.

To the orginial poster, you don't need a high dollar radiator to cool your car. A parts store replacement will work fine.

Aluminum is better for making a nice Mopar engine compartment look like a Chevy's. Never saw one that looks as good as the OE equipment.

I agree that for the OP's purposes a stock style brass radiator will be fine. So would an aluminum radiator. Personally I prefer the stock look under the hood, and that's why I have a stock style brass radiator behind the 360 in my Duster. It always runs as cool as the original slant 6 did.

I never said an aluminum radiator was better; only that the thermal conductivity of the base material of aluminum is better in conducting heat....and not just slightly better, about two times better. The design of the radiator can have as much to do with performance as the base material. Longevity is another issue in and of itself. There are rarely black and white answers to questions such as these and my purpose was to simply point out a fact that may be of interest to someone attempting to make an informed decision. Happy New Year!

Yep, I don't go watch Drag Week because everyone thinks they have to run a Chivvy cowl hood and aluminum radiator.

[quote=justinp61]Tale of two different cars, apples to oranges.

To the orginial poster, you don't need a high dollar radiator to cool your car. A parts store replacement will work fine. [/quote


Apples to oranges? Only difference is the block, same crank, just bigger bore in the 528, same flat tapet cam.

Is'nt that the truth...Even if you made the choice to go aluminum and all else seems well... You need to keep a sharp eye on what's actually circulating through the system...I've seen rads bite the dust with only a few years on them with low/no maintenence..

I worked for two years as an Engineering Manager for a heat exchanger manufacturer.

All HD applications were down in Copper/Brass.

Low cost was done in Aluminum.

Copper/Brass is the way to go.

Tale of two cars, father-sons. Sons, 528 all aluminum Hemi with big aluminum radiator, runs over 2 hundred or more, all the time, with two fans and custom made shroud. Fathers, 472 Hemi steel block aluminum heads stock radiator no shroud, like it came off the line, runs 160 all day, any temp outside. 63&65 Dodges. I told him to get rid of the rad. and electric pump, won't listen, steady throwing money at it??




So both cars have electric water pumps?

Ok, once again a simple question has evolved into a ?? contest. HMM OK let me add my 30+ years of engineering experience to this. No offense meant to the intelligent well informed responses.
In my career I found that water soaked 2x4;s and water logged sheetrock outperformed Brass and Aluminum as long as the car was submerged in straight water. Now, I do have to admit that adding Salt to the water or Ethylene Glycol had an impact on my results.
I Hope someone enjoys the humor in this post,

And aluminum radiators should be dirt cheap due to the quantity of empty Bud Light cans available !!

I'm sorry I guess everyone should make their car the way you want it so you can say it was done right.

My personal experience on the copper/brass vs. aluminum radiators. My 68 Dart GTS, hot 360. I fought a cooling issue for a short length of time. Had a later model A-body radiator, shroud, fan. etc. Everything but the shroud was new, all hoses, water pump, thermostat, radiator, belts, engine was fresh built, fan was new as well. It would consistently run 220 plus and sometimes higher. I actually replaced almost every part on this thing with zero improvement. I tried different fans, water pumps, t-stats, hoses, even another new radiator. Never a single change. Even added a new electric fan added to the front of the radiators. Everything ran the same. Finally, after reading how aluminum dissipates heat faster and more efficient than copper/brass I bought a new one. I even bought one of those cheap units from Ebag. I had to fab up some brackets to mount it. And this was without any kind of fan shroud. I put it in, filled full of collant and I barely ran over 160 again. It could be 90*+ outside and the highest I ever saw it was 170*. I've had the very same experience with my 79 Dodge dually. Had a NEW copper/brass, couldn't keep it cool in the summer with the a/c on. All I did was buy a new aluminum radiator and all cooling issues were gone. This is my personal experience. I will always disagree that a copper/brass is better for cooling.

I worked in a old timey radiator shop in my youth. Your original A-body radiator probably needed riding out as the tubes plug up over time. You wouldn't believe how many old tubes were probably plugged solid... So its likely a new brass radiator would have fixed your cooling problem as well....unless you are saying the radiator was new too? Were they the same capacity/configuration radiator?

Yes, 2 new copper/brass radiators, neither would cool. Aluminum took care of it right away!

Ram charger 4x4 360, 0.30, 9.2:1 compression, stock heads, aluminum intake. Stock radiator 160 thermostat summer time it would over heat on long uphill pulls so I swapped it out for an aluminum perfect fit 2 core which fit near perfect. The width heidth and thickness of radiators are near identical. The aluminum radiatordropped temp two gauge notches. Winter comes along and pow 35 degree days and I get 65 degree heater temps that wont do. I pull thermostate, install 195 thermostats, it runs 1 more notch up the gauge and heater temp is in the 85 degree range. Thinking of going 210 thermostate.
PAGE 78 COOL DEAL MOPAR ACTION
Silver is the best heat conductor followed by copper a close second and aluminum a distant third. But radiators are not made from copper Too soft. So radiators are made from brass a combo of copper and zinc "brass" is half as good as aluminum at conducting heat.
WELL that came from Richard Ehrenburg, SAE that's good enough for me as I have not been steered wrong by his advice tech or articles.

The plot thickens

I had a Ramcharger in the past...

Older truck, 360 also...

OEM cooling config worked fine...


Something else in the mix...

What would the fix be in the past???

Pre-aluminum rad availability...



Been in bumper to bumper, 95+ heat, multiple occasions...

Sometimes for hours at a time...


OEM 'air' system...

20 years of running time...

26" rad, A/C water pump, viscous, 7-blade fan, shroud...

NEVER have seen the temp beyond 180...

G
No, hot one has a Merzzery or however you spell it. I'm saying that's the problem, do you agree?

I agree...I ran my 500+HP Street Car on long road trips over mountains even in summer with a stock water pump and electric fan with zero issues (180-190 degrees +/-). I changed to a 55 GPM water pump and now the cars temp creeps up to 220 +/- even driving around town in dead of summer. I'm going back to the stock water pump...

There are way too many variables involved to answer the question here with anything other than ones opinion, PERIOD!!!

It is not just the material, a few of the other variables are,
Fin Count, number of rows, are they staggered or not, are the fins louvered, thickness of the fins, how many fins per inch, how are the fins attached to the tubes, diameter of tubes, thickness of the tube walls, spacing between the tubes and on it goes.

I'd go with a direct replacement brass unit, you know it will work for years and look proper in your car (not to mention fit correctly without cussing}

I think to many people on here arguing about this subject think that a brass and copper radaitor has brass as part of the liquid cooling system, which it does not. The tubes and tanks are copper and the brass is the thin strips wedged between the tubes to suck heat out of the copper tubes into the air If aluminum radaitors weren't cheaper than copper radaitors are now do you think the car companys would use the aluminum in spite of the costs The aluminum radaitors are cheaper, not better

cab, i hate to disagree with you, as you are a super and respected source of information, but most tanks i have seen in the 50 years i have been playing with cars have been brass. this is especially apparent when the tanks are stripped of paint and polished. just my experience. or are my eyeballs that bad ?

To the OP:

Whatever radiator you choose to run, make sure to do a thorough flush out job of your cooling system before installing the new unit. I would even go so far as to advise flushing out the block by removing the drain-cock or a freeze plug and spraying your garden hose in it for a few minutes until the water runs out clean.

Get all the nasty stuff out that will plug up your new unit.

good point there. I usually end up putting radiator petcocks in place of the block drain plugs to easy future draining. You'll probably find the hole plugged with stuff and will need to poke it loose once you get he block drain plugs pulled.

I have used these for 30 or more years for a very fast and quite good reverse flush. Certainly beats crawling under the car to open jammed up block and radiator petcocks,,or worse yet removing bolt in plugs from the block.

You need not have it installed permanently if for cosmetic purposes,,,just tap unit in before flushing and remove when done. Also flushes out heater which simple draining does not.

I also leave engine idling while flushing. Flush until coolant runs clear out of top of radiator. Always keep water flowing from hose while engine running as otherwise you can damage water pump from lack of lubrication that coolant provides.

Some 15 minutes for whole job. Your cooling system will love you, therefore it will treat you well.

http://www.amazon.com/Prestone-AF-KIT-Flush-Fill-Kit/dp/B000CCFY5W

You don't put drains in the block for flushing, you put them in there to DRAIN the block. You know, get all the coolant/water out of the block. So you don't drool coolant all over the place when you pull a head or something similar. Pretty sure the Prestone flushing kit doesn't get the sediment at the bottom of the water jackets out either. Since I've seen it come out my drains after a flush, draining all the water out for a proper refill.

Aluminum conducts heat twice as fast but needs to be twice as thick so it is a wash. The real issue for functionality between the two is the vast difference in mechanical desighn NOT the material. The OEMs do it in AL because it is cheaper, they also use those stupid plastic tanks on the end because they are cheaper but usually around 5-10 years old they start leaking and need replaced, especially with dex-cool type crap coolant. Many brass radiators (includeing brass tanks) are still in service 50+ years later .

Aluminum 'life' is even less here in the salt mines...

It's been mentioned by other posters to just use the same setup. I agree. You have a stock 318 with AC and it's a cruiser. The engineers in 1971 deemed that cooling system adequate for that combination. They were pretty much correct. Not that there wasn't but I've never read any history of massive issues with cooling a stock 318/AC A-body in 1971. The traditional radiator shop has all but disappeared along with the old guys that knew what they were doing. Otherwise I'd suggest a good boiling or recore job. Just my humble opinion but a stock replacement radiator sounds like the easiest and safest way to go. Why try to reinvent the wheel especially on a stock cruiser.

Petcock draining does not always if ever remove all coolant from the block,,,just ask some of those unfortunates in cold climates who have drained their blocks only to find a cracked block when a small amount of residual water has frozen,,,,just as freeze plugs do not protect a block from frozen coolant caused cracks,,,as most know they are there only to fill the holes that are there to drain sand from the block post casting.

Mere draining also does not normally do a decent job or even a fair flushing of a heater core.

Additionally the Prestone unit described virtually eliminates the all to real possibility of leaving vacuum chambers in your cooling system when filling it.

Flushing and draining both are the best approach of course. How much time do you have?

Did anyone see the latest issue of Mopar Action page 78?

Most people don't consider the emissivity, conductivity take the heat from the water to the radiator, emissivity takes the heat from the radiator to the air...Copper brass has a higher emissivity than aluminum. Ehernberg missed that in his article. Sounded like a griffin advertisement. Griffins cant be welded either, the tanks are epoxied. Unless they have changed their manufacturing in the last 2 years they are not always the best option. Tim

Griffin says aluminum is better, they only sell aluminum. U.S. Radiator says copper/brass is superior over aluminum and they sell both. Talking to a HVAC expert, he says copper/brass coils last longer than aluminum coils.

I'm leaning towards using my OE radiator. Aluminum might look "pretty" and all but my only question is will the OE adequately cool my engine with up to and beyond 500hp with a 190 thermostat and A/C?

The OE radiator is not designed for 500 HP... unlikely a stock radiator will work well for you if you actually use the HP. You need an upgrade in capacity... it can be the material of your choice - either can work - but needs upgraded I think. Good luck!

You combine Hemi, and A/C OEM cooling system components, you'll be fine...