Radiator Dimensions and Cores - Is this a good radiator?

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AuroraGirl

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3 core, has an oil cooler on both sides, is 2 inches thick(the... heighth.. technically...???) while the width and length are 28 1/2 x 19 1/2. this is of the core, not the tanks included.

The one pictured with it is what i believe to be a 3 core thats slightly smaller that went in a car, i think.

Im fidning it hard to find information on radiators or what the capacity of its cooling ability is.
The radiator has solder on the top by the left tank and a couple other spots, so its been repaired before.
Because it sat capped and dry for years, i think i may have good luck with it at the radiator shop. However, because its not as big as the one i brought the radiator shop(which was a big block rad, it was 4 cores etc) I want to make sure im not undersizing the radiator i plan to put in my truck.

Assuming it checks out with the rad shop and they rejuvinate it, would this be a sufficient radiator? And I guess, will it fit? I know gm radiators of the era were pretty darn universal as far as radiators go, but i just want to be sure im not putting a tiny one in.

I had finally got out to my 75 grand am and measured it up.. its a 2 core and the height is very short compared to this one, but its slightly wider. However, it IS 2 inches thick as well... so it has 2 cores but one of them is very thick. I havent seen this. Ill put the photo of the inside of the rad below.
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the one in question is behind the smaller one.

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this is the 75 grand am radiator. 2 cores but one is abnormally large. curious.

thanks ahead of time!
 

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Looks good to me.
What kind of cooling do you think its capable of? Like, I know being optioned with a automatic, AC, high altitude, etc can all change what specs a rad came with a truck. And I dont know what dimension normally is in a square of how many rows or how that translate to cooling since modern auluminum typically have 2 or 3 cores max unless you hit the real upper end, but alumiunum transfer heat energy more efficiently and the cores have thinner passages usually etc so that the cooling per square inch is improved over old brass ones.
Since i want to stick with brass because i already have one and a little more vibration and rough usage resistant, I know that means more radiator = same cooling
 

wanderinthru

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What kind of cooling do you think its capable of? Like, I know being optioned with a automatic, AC, high altitude, etc can all change what specs a rad came with a truck. And I dont know what dimension normally is in a square of how many rows or how that translate to cooling since modern auluminum typically have 2 or 3 cores max unless you hit the real upper end, but alumiunum transfer heat energy more efficiently and the cores have thinner passages usually etc so that the cooling per square inch is improved over old brass ones.
Since i want to stick with brass because i already have one and a little more vibration and rough usage resistant, I know that means more radiator = same cooling

Well, I'm at 4200 feet, in west Texas, and pull quite a bit of heavy things around. All of my engines are 350's with 3 core rads and never have an over heating issue. As long as every thing else is in good shape, fans, fan clutches, thermostats, intake gaskets, tuned carbs and ignition system, and the radiator is clean inside and out. As well as driving habits, run a SBC with 410s esp a standard, 75 mph down a 120 degree interstate it will run hot, slow down to 60 and it will run at the thermostat setting. Far as your automatic tranny question, I do not know, have never had one long enough to know anything about them except they leave your ass walking. Have worked a lot of aluminium in my day, it is a wonderful material, seems people like to use it in places that it is less than ideal, for a truck that runs the roads alum works fine, but when one uses a truck, bouncing around in the woods, across pastures and fields, jerkin on stumps or your drunk buddy to get them out, an aluminum radiator only last 4 or 5 years, my experience. I'll be staying with the old brass ones as long as possible.
 

AuroraGirl

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Well, I'm at 4200 feet, in west Texas, and pull quite a bit of heavy things around. All of my engines are 350's with 3 core rads and never have an over heating issue. As long as every thing else is in good shape, fans, fan clutches, thermostats, intake gaskets, tuned carbs and ignition system, and the radiator is clean inside and out. As well as driving habits, run a SBC with 410s esp a standard, 75 mph down a 120 degree interstate it will run hot, slow down to 60 and it will run at the thermostat setting. Far as your automatic tranny question, I do not know, have never had one long enough to know anything about them except they leave your ass walking. Have worked a lot of aluminium in my day, it is a wonderful material, seems people like to use it in places that it is less than ideal, for a truck that runs the roads alum works fine, but when one uses a truck, bouncing around in the woods, across pastures and fields, jerkin on stumps or your drunk buddy to get them out, an aluminum radiator only last 4 or 5 years, my experience. I'll be staying with the old brass ones as long as possible.
Me too. Thats the kind of use my square has seen its whole life and will continue to see, so its why im trying to stick to brass.

What do your cores measure, by chance? Even a quick eyeball over the shroud just to get close dimensions. thickness i dont think you can do without removing the panel, but if you dimensionally are similar then i should be ok
 

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Other than to say try it a see what happens I*think* a 3 core will be enough, but of course realize anytime you downsize there is risk. As to the second question about the Grand Am any idea if that is a newer radiator? Radiator manufactures claim that allegedly larger rows dissipate heat better than multiple rows. Personally I think suspect is cheaper to manufacture.

Just remember where it comes to radiators, and music, brass kicks ass!
 

wanderinthru

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Me too. Thats the kind of use my square has seen its whole life and will continue to see, so its why im trying to stick to brass.

What do your cores measure, by chance? Even a quick eyeball over the shroud just to get close dimensions. thickness i dont think you can do without removing the panel, but if you dimensionally are similar then i should be ok

In the 84 K 20 28 3/4 center on mounting points 18 1/2 ish tall. In the 81 K 10 started as a diesel, radiator is out of a 78 1 ton same widith yet 21 1/2 inch tall. The 75 C 30 is the same as the K 20. All of these are standard shift tranny radiators. Had one out of a 78 k 10 with an auto around here.....but must have put it where I would KNOW where it is???? Can't find it????
 

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Other than to say try it a see what happens I*think* a 3 core will be enough, but of course realize anytime you downsize there is risk. As to the second question about the Grand Am any idea if that is a newer radiator? Radiator manufactures claim that allegedly larger rows dissipate heat better than multiple rows. Personally I think suspect is cheaper to manufacture.

Just remember where it comes to radiators, and music, brass kicks ass!
it may not be original.. thje car rear ended a school bus in 1992 so depending on how much damage was from that it may have gotten a new one then
 

SirRobyn0

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it may not be original.. thje car rear ended a school bus in 1992 so depending on how much damage was from that it may have gotten a new one then

I don't really remember the larger cores becoming common in replacement radiators until the late 90's but that certainly doesn't mean they weren't around earlier.
 

Bextreme04

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alumiunum transfer heat energy more efficiently and the cores have thinner passages usually etc so that the cooling per square inch is improved over old brass ones.

Not true... Brass is more efficient in heat transfer. Aluminum is cheaper and lighter. Newer aluminum radiators can only match the old brass ones for heat transfer because the fin designs are better and the solder in old brass radiators affects the overall heat transfer.

Bottom line is that a brass radiator and aluminum radiator of the same size will cool almost exactly the same. The aluminum will be cheaper and lighter, but the brass will be far more durable and can be repaired far more easily.

The larger 3-row brass should be plenty for your stock truck. If it can't keep up you likely have a poor running truck or other issues somewhere else in the cooling system.
 

SirRobyn0

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Not true... Brass is more efficient in heat transfer. Aluminum is cheaper and lighter. Newer aluminum radiators can only match the old brass ones for heat transfer because the fin designs are better and the solder in old brass radiators affects the overall heat transfer.

Bottom line is that a brass radiator and aluminum radiator of the same size will cool almost exactly the same. The aluminum will be cheaper and lighter, but the brass will be far more durable and can be repaired far more easily.

The larger 3-row brass should be plenty for your stock truck. If it can't keep up you likely have a poor running truck or other issues somewhere else in the cooling system.

Personally I think one of the hardest things, at least were I live is finding a radiator shop that still works on radiators and is able to repair brass radiators.
 

wanderinthru

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Personally I think one of the hardest things, at least were I live is finding a radiator shop that still works on radiators and is able to repair brass radiators.

It's not just your area.!
 

SirRobyn0

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Another thing I'll say is it seems like the old brass radiators when they had problems the most common thing would be a small to medium leak, you never saw them go from seeming to be fine to split open the next day like the aluminum core plastic tank radiators of today.
 

AuroraGirl

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I don't really remember the larger cores becoming common in replacement radiators until the late 90's but that certainly doesn't mean they weren't around earlier.
Other than to say try it a see what happens I*think* a 3 core will be enough, but of course realize anytime you downsize there is risk. As to the second question about the Grand Am any idea if that is a newer radiator? Radiator manufactures claim that allegedly larger rows dissipate heat better than multiple rows. Personally I think suspect is cheaper to manufacture.

Just remember where it comes to radiators, and music, brass kicks ass!
the grand am radiator is 28 x 19 or so, very close. 2 cores, brass.
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The tanks are pretty large too. Kinda weird its so big, but only 2 rows, but large tanks.
 

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