Radiator Size ????

Yeah, not all that is true.

Two cores with big tubes will not always out cool 3 cores with smaller tubes. You actually have to do the math, figure out the surface areas, flow rates, number of fins, all of that. There are 3 core radiators out there that will out cool large tube 2 cores. The factory ran 3 core radiators too!!!

There are two major gimmicks in radiators at the moment. One is more cores, the other is big tubes. The companies that just add cores will sell you a 4 core radiator and say it's the best, despite the fact that the air going through the radiator is slowing down and heating up, making the additional cores less efficient as they go. The companies that add giant tubes will say they're best, despite the fact that they may actually be losing surface area, or that the large tube will not cool as efficiently all the way across that larger cross section. Both styles can become less efficient as things get extreme.

Bottom line is, "bigger tubes!" is as much a gimmick as "more cores!" if you're not actually checking the numbers and doing the math. A well set up 3 core can out cool a poorly set up large tube 2 core, and a well set up large tube 2 core can out cool a poorly set up 3 core. I would stay away from 4 cores just because of the overall thickness of the radiator, which can also be an issue with the really large tube 2 core radiators. It does have to fit in the car.


Easy, poorly set up cooling systems for both electric and mechanical systems. Want the Reader's Digest version?

-Electric fans that don't move enough air (expensive does not equal good)
-Mismatched pulley's under driving the water pump
-Wrong water pump for the pulley ratio (factory ratio .95:1 pumps had 8 vanes, factory 1.3:1 ratio pumps had 6)
-Poorly controlled electric fans (manual switches and temp probes are not great)
-No shroud (mechanical or electric), fan not covering enough surface area or pulling across the entire radiator

And you can even throw in mechanical fans that are too small or don't have the right number/shape of blades (they're designed to work at a certain RPM), electric fan systems with wiring that's too small or with alternators that can't provide enough juice to meet the specs, plugged tubes, radiator hoses sucking closed, thermostats not opening correctly (or removed altogether), internal engine passage issues, etc, etc.

But people that slapped together a poorly thought out electric fan SYSTEM will say electric fans suck. And people that spent a brick on a fancy radiator will say cheap radiators can't work either.


Exactly!

The OE Ford Contour fans work best on a 26" radiator. I love mine, my car will run at whatever temperature I program the fans for as long as the thermostat matches that temp. And I just run a standard thermostat, the 8 vane pump correct for my pulley ratio, and a Champion 26" 3 core radiator. There are a lot of ways to set up a good system, and even more ways to set up a bad one.


Right. I’m talking about a correctly engineered two core.

I haven’t been to a circle track in a while (because I’m not a fan of that and unless I’m there to tune something I don’t go) but virtually every car that doesn’t have issues under caution (where far more cooling issues occur) runs an overdriven water pump and a two core radiator. And they have a tune up that isn’t stupid. And if they really have their poop in one group they are running vacuum advance.

And the opposite is true. The cars that overheat under a yellow have multiple smaller cores, double and triple pass junk **** and underdriven water pumps. And if you dig in, you’ll see they don’t have a vacuum advance, a locked out distributor and some crazy thing like 32 total, that even running at 3k is probably retarding some.

So the answer always is buy the biggest two core radiator that will fit (one that is correct designed), overdrive the water pump and get the tune up correct.

You also have to consider what happens when the cores are smaller. How much more restriction does that add to the system? I don’t know but someone with good math skills could probably get close.

If a 55 GPM water pump loses near 50% of its capacity with a high flow radiator, how much more restriction does a 3 or 4 core add?? Then add in the horrible double pass or worse yet the hideous triple bypass.

You add so much restriction to the system you still don’t have the coolant flow.