72 fitment aluminum radiator into a 1974?

Ccas said
Our claim is that 2 big row aluminum cools better than 3 5/8" rows in aluminum. The claim is generally true. Not generally false. While there are other factors like (air flow and engine hp) that could make this claim false, the claim is generally true. We have done engine testing on radiators with 2 big row vs 3 small row, tri-flow, dual flow, same side inlet, crossflow etc changing only the radiator that 'generally' support our claims but the best proof I can offer is that of aluminum 3 row customers switching to 2 Big rows and experiencing lower temperatures. This is public information by real people found all over the internet.
1. A 3 row 5/8" aluminum radiator doesn't hold as much fluid as a big 2 row.

2. The flow of air through the radiator is restricted by the thickness of the radiator and the friction produced between each row.

3. Because the surface area of the tubes are smaller, the transfer of heat is not as efficient as the transfer of heat of the larger tube surface area of the big 2 row.

All of this is comparing aluminum to aluminum.

If you did testing, let's see the actual results. Test parameters, radiators tested, actual temperature data. Not just a vague statement about your customers having lower temperatures after switching. If you've got the data, show it.

1. How much volume does each radiator hold? You should have that info.

2. Yes, in general, the air slows down and heats up as it passes through the radiator. The air warms as it passes each row, the thicker the radiator the more it slows the air. But how much that actually effects efficiency and performance depends on a lot of specific design element. And it doesn't necessarily mean adding an extra row is inefficient, just that it's less efficient than the first one. The 2nd row in a two row radiator is also less efficient than the first, yet we still use 2 row radiators. You're balancing the increasing temperature and slowing air flow with the additional surface area of the next row of tubes. If the surface area of the tubes wins out, the next row improves the performance of the radiator.

3. Again, you should have the actual surface area information, so, lets see it. That's where the rubber hits the road. Does your 2 row "big tube" radiator have more surface area than the 3 row radiators you're talking about? Prove it.

Ccas said
I didn't say all radiators. I said 3 row aluminum vs 2 big row aluminum.

And as far as your car, certain vehicles simply don't need additional cooling capacity. Your 3 row copper 26" radiator with a 318 stock motor would probably run fine on even a 'small' 2 row aluminum radiator. It certainly would run fine on an aluminum 3 or 4 row. I make claims (opinions) based on the situation and based on the experience we have. For example, you'll never see me tell a factory 318 owner with a 26" 3 core copper radiator that he's making a mistake by getting a 3 row aluminum radiator and that he absolutely needs a big 2 row. I might recommend a big 2 row radiator for the weight savings, nicer look, future motor upgrade or just plain piece of mind in a situation like that, but generally I you'll notice I rarely if ever make a specific recommendation for any of our radiators.
My advice is normally very helpful, unbiased and accurate.

It's very appropriate for readers to know, that in general, 3 row and 4 row aluminum radiators are LESS efficient than Big 2 row aluminum radiators. The viewers can apply the specific circumstances of their situation like cost, engine hp, fan air flow, spacing, driving habits, gear ratios, transmission cooler and more to make an educated decision on the best option.

What my car would run on isn't the point. It has a factory three row radiator. It came with one because that's what the factory used to increase cooling capacity when they did things like add AC and automatic transmissions. You think the factory would have bothered if they could have used the same two row as came in models without AC? You know they wouldn't have.

Your lack of specific recommendations is exactly the problem I have with your claims. Your general claims are false. If your radiator cools better than your competitors, say that. And back it up with numbers, not general claims.