Correct Radiator

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custodian

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I stated the wrong info earlier in this post, My support has a place for mounting 2 different radiators not 3.

This is my radiator support from my 85 C10 2wd that originally had the 6.2 diesel. The radiator sitting there is a CU161 17" core, which is supposed to fit the square body trucks. You can see the big difference, about 2.5".

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custodian

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I had a 730 in my '79 K15 (stock 350/TH-350/A/C). No issues with over heating. The capped fitting you see should have had a heater hose going to it. The PO had the hoses hooked up wrong. It's not pictured very well, but the top plate for the radiator support was flat.

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So, if one of the heater hose hooks to the radiator, is the fitting spot on the water pump plugged off? My truck will have the AC fixed, next year, so would like to route the heater hoses to the correct place.
 

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Here the info from Summit Racing. The bigger radiator is cheaper.

716 - $166.99
Inlet Location:Upper driver side
Outlet Location:Lower passenger side
Core Width (in):28.250 in.
Core Height (in):19.313 in.
Core Thickness (in):1.250 in.
Row Quantity:1
Transmission Cooler:Yes
Inlet Size:1 5/16 in.
Outlet Size:1 9/16 in.

730 - $132.99
Inlet Location:Upper driver side
Outlet Location:Lower passenger side
Core Width (in):28.375 in.
Core Height (in):20.250 in.
Core Thickness (in):2.250 in.
Row Quantity:2
Inlet Size:1 5/16 in.
Outlet Size:1 9/16 in.

I found that info. Leaning towards the 730.
 

Craig 85

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So, if one of the heater hose hooks to the radiator, is the fitting spot on the water pump plugged off? My truck will have the AC fixed, next year, so would like to route the heater hoses to the correct place.

Yes the water pump would be plugged.
 

TPISly-C10

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The 6.2 radiator would do a better job cooling, but if it's doesn't have port for the AT, then I guess you gotta do something else.
agree!! i keep the Diesel rad on my LS 6L swap fit pefect and run cool! :)

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austinado16

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Was gonna suggest the same thing. You have the real estate, go with the big 19x34 radiator. I believe they're available in both OE brass/copper, and plastic tank with aluminum core. I've done the upgrade from the "standard" SBC radiator, to the same width, but thicker 454 version, and then finally to the 34" long version that was used in the 2WD 454's and the diesels (but the diesels have different tanks that have much larger diameter fittings). I put together a thread on my upgrade: https://www.gmsquarebody.com/threads/upgrade-installing-the-longer-2wd-3-4-ton-454-radiator.15474/

I'm not saying that what I did is the best solution, or the ultimate solution. I'm just showing what I did. I was doing a lot of towing up and down 7,000' grades, at speeds in the 25-35mph range due to who twisty the 2 lane roads were, and generally in temps that were in the high 80's to low 100's. Sometimes, that climb included 8 or 9 people and there gear on board.
 

custodian

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Was gonna suggest the same thing. You have the real estate, go with the big 19x34 radiator. I believe they're available in both OE brass/copper, and plastic tank with aluminum core. I've done the upgrade from the "standard" SBC radiator, to the same width, but thicker 454 version, and then finally to the 34" long version that was used in the 2WD 454's and the diesels (but the diesels have different tanks that have much larger diameter fittings). I put together a thread on my upgrade: https://www.gmsquarebody.com/threads/upgrade-installing-the-longer-2wd-3-4-ton-454-radiator.15474/

I'm not saying that what I did is the best solution, or the ultimate solution. I'm just showing what I did. I was doing a lot of towing up and down 7,000' grades, at speeds in the 25-35mph range due to who twisty the 2 lane roads were, and generally in temps that were in the high 80's to low 100's. Sometimes, that climb included 8 or 9 people and there gear on board.

I read your post.thanks for the info. I'm going with the 730, 454 radiator. This truck will be given to my youngest granddaughter, 15 years old at the time, when she turns 16.
 

AuroraGirl

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Yes the water pump would be plugged.
my 1980 used the water pump as normal but the radiator and the intake got coolant. it was spliced into the one that goes to the manifold i think
 

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I received my Spectra 730 radiator today. Might be able to use my diesel fan shroud, would have to cut a hole on drivers side for the upper radiator hose.

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AuroraGirl

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Doesnt have to be this minute but i suggest, since youre building this truck for your daughter who is a teen, its gonna be like a new truck.
and damnit, if she is good she will appreciate the HELL out of this, so thank you for doing it.

But anyway, its gonna be a long term ownership kind of thing.

I suggest maybe finding a high quality two piece shroud so its ease-of-repairs down the road are better, unless you have electric fans in mind.
If I build any project, its definitely being put together for the next person(most likely me) ease of repair. My grandpa was more "not my problem" and just sent it.

He didnt have to worry about it in his lifetime.


He wasn't wrong lol
 

Bextreme04

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Doesnt have to be this minute but i suggest, since youre building this truck for your daughter who is a teen, its gonna be like a new truck.
and damnit, if she is good she will appreciate the HELL out of this, so thank you for doing it.

But anyway, its gonna be a long term ownership kind of thing.

I suggest maybe finding a high quality two piece shroud so its ease-of-repairs down the road are better, unless you have electric fans in mind.
If I build any project, its definitely being put together for the next person(most likely me) ease of repair. My grandpa was more "not my problem" and just sent it.

He didnt have to worry about it in his lifetime.


He wasn't wrong lol

Lol, as long as it works... right?

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austinado16

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That radiator definitely fits better. Is it long enough to fit the diesel shroud? That looks more like the width of the BB/SBC radiator with a 28" core. If so, the standard deep SBC shroud should work if you have a SBC, and the shroud "should" flare rearward enough to cover the majority of the fan blade pitch. That shroud also has a built in closing panel I think, for across the top of the radiator (maybe I'm not remembering correctly how mine originally was built). Otherwise if you have a BB, the shallow dept BB shroud and the separate steel closing panel "should" work.
 

AuroraGirl

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That radiator definitely fits better. Is it long enough to fit the diesel shroud? That looks more like the width of the BB/SBC radiator with a 28" core. If so, the standard deep SBC shroud should work if you have a SBC, and the shroud "should" flare rearward enough to cover the majority of the fan blade pitch. That shroud also has a built in closing panel I think, for across the top of the radiator (maybe I'm not remembering correctly how mine originally was built). Otherwise if you have a BB, the shallow dept BB shroud and the separate steel closing panel "should" work.
correct. forces air to be pulled in front of it rather than sides of radiator
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in the case of this grand am, its the shroud double duty
 

custodian

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That radiator definitely fits better. Is it long enough to fit the diesel shroud? That looks more like the width of the BB/SBC radiator with a 28" core. If so, the standard deep SBC shroud should work if you have a SBC, and the shroud "should" flare rearward enough to cover the majority of the fan blade pitch. That shroud also has a built in closing panel I think, for across the top of the radiator (maybe I'm not remembering correctly how mine originally was built). Otherwise if you have a BB, the shallow dept BB shroud and the separate steel closing panel "should" work.

The diesel fan shroud is longer that the radiator. I don't have a fan shroud yet. I bought this as a BB radiator but using it for a SBC. I have the piece that goes across the top of the radiator, but it too is for a diesel.
 

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