Since 455 install, 2 (two) aluminum radiators from the same builder developed leaks. I'm hesitant for them to send a third (warranty covered.

With that said I have been looking at a beautiful copper/brass one that fits my application.
Would this be a good choice?

THanks for all the conitnued help

my 455 / 1968 cutlass convertible

 

US Radiator - US Radiator

or

Obtain a Harrison core and have it re-cored.

 

is that aluminum ?

 

No

 

Cold Case and Be-Cool both make excellent aluminum radiators with similar-to-OEM core design for more of a factory look

Be-Cool also makes their GM retro-fit unit in black if you want to keep it in theme with how the factory did it - I have that one in my ragtop now and it looks/functions excellent. Rarely ever see above 180* in Florida heat and that's without electric fans.

 

A radiator repair shop near me just repaired/rodded and cleaned/pressure tested an original brass radiator I had as a piece of flange on the neck broke. I asked him his opinion on the all- aluminum rads. He told me he has a lot more of the aluminum "performance" ones come in for repairs due to cracks. He wouldn't say which brand, though. He said those aluminum/plastic late-model OEM ones are normally cheaper to replace than repair so he hardly ever does any work on those. There's not too many more old-school rad repair shops around, though. Last of a breed.

 

I put a Cold Case radiator in my 75 W30 Hurst Olds last year after we got back from the nationals. It was a perfect fit and dropped my temp by about 20°. They now make a black one that looks stock.

 

The Be cool in my car is 20 years old, it’s been flawless. Unless the quality has gone downhill over the years, if go aluminum. All things being equal, aluminum cools better.

There is a reason the OEM stopped using copper.

 

Actually copper has almost twice the thermal conductivity than aluminum 401 W/mK vs 237 W/mK
Yes, It was cost and weight.
Copper cost 4x as much as aluminum $4.57/lb vs $1.20/lb
Copper weighs 3.32x more than aluminum. 559.87lbs/cuft vs 168.48lb/cuft

 

Copper does transfer heat better, but it’s also much weaker. Meaning you can make the tubes larger with aluminum, resulting in more surface area, and better cooling in the same space.

 

Design has as much to do with radiators as the heat transfer capabilities. If everything except material was equal, I'd go with copper every time. It has twice the heat transfer coeffiecient than aluminum. You have a limited amount of space to fill. Problem with most aluminum radiators is they don't even bother using larger tubes. They still go with the small tubes. Here again, it's quality over quantity. If you buy cheap stuff, it doesn't matter what it's made of. Like every other part, get quality units whether copper/brass or aluminum.

Take care of either of them and they should last a long time.

 

Yeah, heat exchangers are more complicated than just thermal conductivity. Conductivity matters, but honestly, with typical radiator design, it isn't as critical as you think. A year or two ago I had to do some preliminary sizing of a heat exchanger for an aerospace application. Thermatron is a heat exchanger supplier that has a lot of performance data readily available on their tube/fin cores. They also have the exact same cores available in stainless steel and copper. There's a full order of magnitude difference in thermal conductivity (16 W/mK vs 400 W/mK). The performance of the stainless steel version is 70% of the copper. The difference between aluminum and copper is much less. So you're arguing over a few percent.

This topic comes up a lot with people attempting to argue minutia. The truth is, either one will cool a typical street engine without issue. If you are making a lot of power, you probably don't want the weight of copper/brass, and aluminum is perfectly capable of cooling insane power levels. If you're an OEM, as pointed out, aluminum is also cheaper. Its worth pointing out that super heavy duty equipment (think mining vehicles) still use copper/brass radiators.

For quality, it comes down to who is building it. Plenty of quality aluminum radiators out there. Plenty of crap ones too. Buy from a quality vendor (regardless of material choice), do the proper maintenance (corrosion inhibitors in your coolant don't last forever), and you'll likely be fine.

 

My old car specialist mechanic main business is radiators. “Best place in town to take a leak”. Solid, experienced and practical.

They’re solidly on the side of copper brass, but my old cars run just a little hotter than I’d like. I’ve been curious about aluminum for my ‘66 big cars for say, 30 years or so, but have never taken the leap. I can swing a few hundred $ for an experiment I’ve been interested in for so long.

Anybody have a reference or URL for onshore (USA made) ‘66 Olds big car radiator I could try to see if I like it better? I believe the cores are 28” or overall 33” wide and maybe 18.5” tall. Both cars are factory style with the all 4 rubber front curtains to force air through the core. And both cars have modified-to-cover-the-whole-core 1966 rear shrouds. I’ve gone waay out of my way to get the most out of the factory copper brass original design.

The short version is I radiatored & shrouded both cars as if they were both Hi-po A/C cars which pretty much makes up for our cr*ppy alcohol gas and warmer world.

Living near SF in CA, we get a couple of weeks per year of 90+°F, so I go out of my way to keep the old cars cool. Right down to 70/30 distilled water/antifreeze mix + 2 bottles of water wetter in my 17.x quarter systems.

In both cars (‘66 Starfire w/ A/C, ‘66 98 w/o AC) I’m running high fin density 4 core copper brass radiators now & have forever. But I remain curious about whether aluminum could perform better and last.

Views?

Not trying to incite a flame war, just curious about your experiences. There’s lots of room for difference experiences, I’d just like to hear you tales. Jump in!

Cheers
Chris

 

FWIW, I'm running a BeCool retrofit radiator in my '72 and it has been a tank. It's been R&R'd dozens of times in the past ~8 years and has been beaten up a lot. There's a bunch of punched fins, and some spots where something has clearly tried to push through the tubes.

No leaks! I'm quite impressed. I have a knack for breaking stuff, so anything that lasts a few R&R's around here is solid quality.

w.r.t. copper vs aluminum, I bet copper is MUCH easier for a shop to work on so they'd prefer that. But the material cost is horrible now. In the end, a well made 2 row aluminum and a 4 row copper are very comparable to the point that other attributes (cost, fit, looks, etc) probably matter more.

 

Yes, nothing better period. Our cars were put together to last...

Not surprised, sounds like a solid shop. Thats not swayed by shiny parts and weight savings motivations. That modern notion that newer is better does not translate well on 64-72. Unless you truly don't respect the era.

Swapped a Modine 951 into my 87 442, and proceeded to flog it at the track for years. No complaints, good aluminum rad. But the Harrison in my 69 still gets the job done 56 years later...

At 110,000 miles and 50 years old the 69s Harrison heater core went. Bought a local parts store replacement. And added pressure to the system by going with a Flowkooler hi-flow. The new heater core lasted 10,000 miles then started leaking after my last track session. Now another 20,000 miles later, stock stamped Harrison radiator is still getting the job done... knock on wood.