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Thomas Fournier

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Hello all,

Im looking to replace my old 4 core copper/brass large radiator. After repairing it with solder and or just crimping it multiple times in the past..its time for a new one (it just sprung a new leak on the top). Im game to spend some extra money on a radiator that will last as long as this one (about 20 years). What brands are any good anymore?

i was looking at this one since I've heard good things/good reviews on mishimoto radiators...

https://www.summitracing.com/parts/mio-mmrad-cam70x

Or just the summit brand??? Or maybe the lmc truck brand??? No one really sells the copper type anymore.

think its worth getting the huge one with three rows? Or just a "regular" size one with 2 rows?

I know this is really a three part question so bare with me lol

mind you im running a 77 chevy with a small block, th400 4wd 4.56 gears and 37's. Just want something reliable.

Thanks for the help,
Daniel
 

mrk5

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I've had 2 aluminum radiators fail so I've gone with what they sell as standard replacements these days. Last couple I bought were the plastic tanks with aluminum core by Spectra. They've worked fine. I think if you really want a quality all aluminum radiator, you need to be prepared to spend big money.
 

Ned Kelly

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Spectra cu730 plastic tanks and aluminum core going on 12yrs (on a 454) Made in Canada.
Spectra cu730 with plastic tanks and aluminum core has worked well for the last 5-6yrs (on a 350). It was from $110 from Summit. Made in China.


Description:
w/ A/C Or Heavy Duty Cooling; w/ TOC (Transmission Oil Cooler); w/o EOC (Engine Oil Cooler); 28-3/8 in. x 20-1/4 in. x 2-1/4 in. Core; Replaces OEM 4 Row Core; Radiator Cap Is Required
 

TreeFarm

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Whatever you do, do not buy a Griffin radiator. I had 4 fail on me in less than a year, all in the same spot. Where the tubes mated to the end plates. Replaced under warranty sure, but that involved waiting for summit to ship me one, and me to ship the old one back. Calling griffin directly resulted in them just telling me to call summit, they don't want to deal with it. That thing did cool pretty damn good though.

Since then I buy a part store brand with a good warranty. If it fails you can just pick one up at the local store.
 

anwat

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My vote goes with the Mishimoto CK78x. Don't buy the shroud, though. I would recommend sticking with the engine fan. The customer service at Mishimoto is as good or better than Summit, and the radiator is a quality piece. I had some issues with the shroud, Summit sent me to Mishimoto, and they made good on it without an issue. The radiator works great, is solid and most importantly, cools better than anything I've seen. I've got some big gaps around the hoses (the shroud issue) which let a lot of air in, and my truck never goes beyond 230, even uphill in death valley going 20-25 mph. Had it for about 5 years, looks new inside and out, no issues whatsoever.

The spectra cu730 is also a good radiator on paper, it's built with two one inch tubes, so it should offer the best cooling possible, and it's less expensive. I bought one, but couldn't get it to fit in my k5, so I sold it to a buddy who put it in his sub. It's only been there a couple of years, but so far no issues with that one either.
 
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2Dogs

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I used Spectra (CU774) on my last project. Good enough and you get what you paid for from my view.

However - packaging was complete shit and I had filler neck damage on 2 shipments. On the second I just had the neck replaced on my own dime. The repair shop said Spectra uses minimal solder on the builds and the aluminum/plastic models were better but when I asked him to get one he could not locate one within reasonable time or price....

Order from a parts store (might cost more) so they can deal with the damage and return if it happens.
 

mrk5

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The last time I ordered a radiator for the crew cab, Summit ended up sending me 3 radiators due to shipping damages. The one in the truck now had a little damage but not enough to affect performance. I was tired of dealing with receiving damaged radiators so I just ran it.
 

skunked

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I went through the same crap with a spectra fuel tank. They don’t support the filler neck properly in the packaging so the neck cracks at the tank during shipping.
 

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I haven't done a radiator in my "classics" for a few years. I have in the past just had my tanks re-cored. I have several done with Craig mfg cores, the business is in So cal, not sure whether imported or made here. 3 of my Craig re-cores are 15 to 20 years old. The cores have higher fin per inch counts, than discount aftermarket replacements, sometimes more than oem.
I like to keep my brass stuff brass, helps keep electrolysis manageable.
If you have aluminum intake, and or heads, then there is no reason to stay with brass, thou I would also change the heater core to aluminum
 

dyeager535

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I like to keep my brass stuff brass, helps keep electrolysis manageable.
If you have aluminum intake, and or heads, then there is no reason to stay with brass, thou I would also change the heater core to aluminum

I'd certainly like to as well, but unfortunately it's not like the old days. You can buy five of the plastic/AL pieces for the cost to recore anymore.

Lost both my radiator and heater core (brass, 20 years old) recently. I tried to play the testing antifreeze and top off the additive package game, but based on the radiator that wasn't working. Honestly while a pain for me to dispose of, the changing of antifreeze at 5yr/150k isn't a whole lot of cost, and something most do anyway, really no reason regardless of what the composition is of the engine parts to have any issues if using proper coolant, and changing at the correct intervals.
 

diesel4me

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Mt friend uses a lot of Spectra radiators at his shops and has only had a few go sour in short order...several came damaged out of the box though,and he gets most of them from AutoZone or a direct distributor of Spectra products ..

I kept a few OEM radiators from trucks I parted long ago,but the better ones with 3 cores ended up becoming a mouse condo in my shed..their urine finished them off big time.:angry1:...I got $15 each for scrapping them..

I know of one junkyard that has probably hundreds of old OEM brass radiators in good condition,they filled 2 school buses with them--only bummer is most have no markings to ID what they came from,but GM used the same radiators in square bodies as many of their cars in the 70's and 80's,vans too,so they likely still have a good selection of them..
 

Thomas Fournier

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You guys rock! So much information.

Ive heard mixed stories about electric fans v engine fans...i guess ill keep the stock three blade clutch fan.

I want to lean towards the spectra plastic/aluminum due to the price but i dont wanna get burned with the shipping issues. Anyone have first hand experience with the mishimotos? the be cools seem good too and not too expensive.

what do you guys think about size though? I have the larger of the sizes. Is it worth getting the big one or the "standard" size one? what about the two core v three core debate? Seems 4 core only works good with copper brass style radiators...
 

Wes Harden

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2 large tube rows, should be better than 3 or 4 average size rows, in aluminium. Shouldn't be hard to source a spectra local for you.
 

Ned Kelly

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Spectra is available at many local parts stores. I will be buying a 3rd one soon for another truck.
 

broflow

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I recently put a Coldcase radiator in. I think they are a relatively new name? Bought it from summit or Jegs can't remember. It wasn't the cheapest nor the most expensive. Its an aluminum large 2 row and was a direct replacement for a late 90s gm truck. I had to build some custom mounts for it but it wasn't to hard to fit in. It was the widest one I could find. My thoughts were mor
e area more cooling. I believed it has about a 35" wide core so I have enough room for 2- 16" electric fans if needed. So far its working great with 2 - 12" electrics. It has a real nice finish and the welds look top notch for what its worth? It also came packed in quality package with foam packing all around it so it was as it should be when it arrived. Only time will tell if it holds up? I'd recommend.
 

dyeager535

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Ive heard mixed stories about electric fans v engine fans...i guess ill keep the stock three blade clutch fan.

I want to lean towards the spectra plastic/aluminum due to the price but i dont wanna get burned with the shipping issues....

what do you guys think about size though? I have the larger of the sizes.

OEM electric fans work. Why Windstar fans are a popular swap. But realistically I think the stock mechanical fan setup is good. You can upgrade using "factory" parts, as there is an HD clutch out there, and there are fans with more blades. A three bladed fan is going to struggle against the five or seven blade ones that were more common later on. Both should be bolt on swaps, and they won't hurt reliability. Electrics are good if you ford water deep enough to reach the fan blades, or if you idle a bunch in very hot weather and want the AC to work as best it can. There is absolutely no measurable economy savings going with an electric setup, even though I know manufacturers like to say there is. If you were racing, sure.

I personally don't think I'd get bent out of shape about the name on the plastic/aluminum radiators. Even the Spectra's are coming from china now, and if I was going to buy a plastic/aluminum unit, I'd want to be able to swap it out at the parts store. My first one failed as soon as I fired the engine up, the second one has been in there two years now.

Changing size of the radiator is going to introduce a host of issues such as mounting brackets, fan shroud modifications, etc . If the present size has been working and will likely work for what you have planned, dont sweat it.
 

Thomas Fournier

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OEM electric fans work. Why Windstar fans are a popular swap. But realistically I think the stock mechanical fan setup is good. You can upgrade using "factory" parts, as there is an HD clutch out there, and there are fans with more blades. A three bladed fan is going to struggle against the five or seven blade ones that were more common later on. Both should be bolt on swaps, and they won't hurt reliability. Electrics are good if you ford water deep enough to reach the fan blades, or if you idle a bunch in very hot weather and want the AC to work as best it can. There is absolutely no measurable economy savings going with an electric setup, even though I know manufacturers like to say there is. If you were racing, sure.

I personally don't think I'd get bent out of shape about the name on the plastic/aluminum radiators. Even the Spectra's are coming from china now, and if I was going to buy a plastic/aluminum unit, I'd want to be able to swap it out at the parts store. My first one failed as soon as I fired the engine up, the second one has been in there two years now.

Changing size of the radiator is going to introduce a host of issues such as mounting brackets, fan shroud modifications, etc . If the present size has been working and will likely work for what you have planned, dont sweat it.



That sounds very reasonable. Seems all the stuff these days is cheap china made anyways. I might just swing to the parts house and snag a stock replacement and see what happens. I am going to run ac soon (when i get to installing it) so maybe down the road electric fans are a future expense for that cali heat. I think im just going to replace the radiator and leave it the way it is. Its never overheated the way it is so i dont fix what isnt broken lol

thanks for the help all!
 

anwat

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Not to muddy the water, but Mishimoto does offer a lifetime warranty that even covers crashes. While I'm sure they are made in some faraway place, their corporate and research facilities are all here in the US, as is the customer service. When I called, the guy helping me actually knew about cars, and had a mustang that he built himself with mostly Mishimoto parts, so he actually spoke English and knew what he was talking about. I also know I used the cardboard from that radiator box for about two months to keep me clean when I was laying in the dirt under the truck...it was packaged like a 300 dollar radiator should be. It's a drop in for your truck, also. Only downside is that it's three rows instead of two. As @weshardin already mentioned, two is the most effective in most setups. But it is going to cost a couple of hundred more. Just wanted to throw out that warranty part since no one had mentioned it.
 

Thomas Fournier

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Not to muddy the water, but Mishimoto does offer a lifetime warranty that even covers crashes. While I'm sure they are made in some faraway place, their corporate and research facilities are all here in the US, as is the customer service. When I called, the guy helping me actually knew about cars, and had a mustang that he built himself with mostly Mishimoto parts, so he actually spoke English and knew what he was talking about. I also know I used the cardboard from that radiator box for about two months to keep me clean when I was laying in the dirt under the truck...it was packaged like a 300 dollar radiator should be. It's a drop in for your truck, also. Only downside is that it's three rows instead of two. As @weshardin already mentioned, two is the most effective in most setups. But it is going to cost a couple of hundred more. Just wanted to throw out that warranty part since no one had mentioned it.
Interesting you say that cause the two row us cheaper..

https://www.summitracing.com/parts/mio-mmrad-cam-70

its basically the same size but not as thick. I might do this one.
 
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