Radiator Size ????

[72bluNblu]

Slowly block off the electric fan and it will start to slow down. That is a condition of stall.
And what does it do when it starts to stall? Yeah, you guessed it, it's output is reduced.
So please, don't go telling me what it isn't. ok?
You can talk all the CFM you like but under how many inches of h2o is that CFM being achieved?
No point having a fan that has 4500 CFM free flow, just to find it only has 1000CFM once it's put up against the radiator.
I'm not going to bother getting into the nuts and bolts of cooing systems and how to effectively set them up, because this place does not pay my bills, but I can see from this thread that most people have zero idea how to do it.

Yeah so if you blocked off a radiator the electric fan behind it would definitely lose output, but it wouldn't be because of the rpm the blades were spinning. You might actually get a stall, but that would allow the rpm to remain the same/similar while the output reduced. You're not going to bog an electric motor like that in the real world. The rpm might vary slightly with the air resistance, but the picture you're painting of the motor winding down is not at all accurate.

As far as the rated CFM, on that we agree. You're at the mercy of how the company rated its fan, the published spec is not likely to be under the same conditions as what you'll get mounted to a radiator. But unless you're going to buy a dozen fans and test them yourself, well, you're SOL. So, all you can really do is consider the published CFM and go from there. If the rated CFM is less than the mechanical fan you're replacing, you have no chance at all. If it's higher, well, it should work as long as the manufacturer hasn't spoofed their numbers. But that's true of everything isn't it?

Most people don't have an idea of how to set up a cooling system, or even the things they need to be considering, which is why these threads always devolve into guys yelling about bigger tubes or how all electric fans suck because they couldn't get theirs to work. But I don't think you're going to dazzle me with the "nuts and bolts" either, given the inaccuracies you've already posted.

I agree there BUT... look at the size of the radiator for a V6 as compared to that of a 60s 70s V8. The V6 is huge compared.

There's a lot that goes into that. The power per cubic inch of a modern V6 is much higher than the old V8's, which means more heat in a smaller package. There's also the design of the car. Like if you look at the Ford Contour V6 I pulled my electric fans from you'll see they have a TINY grille opening, and the engine compartment is packed solid end to end. So, even though the engine is smaller, the fans are pretty awesome.

 

[Bakerlite]

Yeah so if you blocked off a radiator the electric fan behind it would definitely lose output, but it wouldn't be because of the rpm the blades were spinning. You might actually get a stall, but that would allow the rpm to remain the same/similar while the output reduced. You're not going to bog an electric motor like that in the real world. The rpm might vary slightly with the air resistance, but the picture you're painting of the motor winding down is not at all accurate.

Lol, sure whatever you say. The motor rpm will stay the same under full fan load or no fan load.
If the fan is still spinning flat out, where is all the flow that it should be producing?

"Fan stall occurs as the fan reaches its stable operating range limit. This happens when the pressure rise across a fan increases to the fan’s pressure developing limit and the flow velocity though the fan reduces to the point at which it first falls to zero and then reverses. As the flow through a fan reverses, it separates from the fan blades with the turbulence that occurs with the separated flow buffeting the fan blades. This aerodynamic buffeting induces an increase in unsteady stress within the blades that can result in mechanical failure.
As a fan approaches stall, the separated flow initially occurs with one blade passage. Stall in one blade passage increases the aerodynamic blade loading on the adjacent blade passage, with a consequence that the “stall cell” moves to the next blade passage. This results in a cascading effect as a stall cell jumps from blade passage to blade passage. The shape of and distance between fan blades affect how the stall impacts fan performance with more highly aerodynamic loaded blade designs suffering a more severe reduction in performance during stall than lightly loaded designs."

The fan slows, then goes into stall.
Carry on..enough spoon feeding for today.

 

[Oldmanmopar]

The barracuda pictured above has a 408 stroker with 12-1 compression . Full exhaust and AC. It is running a factory 7 blade fan and a non AC factory dual core 22 inch 1967 50 year old radiator.

Before we installed the 408 it had a fresh 340 with a aluminum radiator huge high flow fan and no AC, You couldn't go 3 bocks and it was over 3/4 on the gauge . It was not the radiator. It was the fresh engine was built by an idiot at Koffels Engines. We got the receipts with the car from a member on this site. gtsjohn

Now it runs very cool and takes a while to warm up driven on the street with 391 gears. Sitting in traffic it never goes over 1/4 on the factory gauge. Any Aluminum radiator 22 inch is sufficient. You cannot flow any more then the hole in the rad support anyway unless you cut the hole bigger. Bad compression rings will make the car run hot. Also exhaust header or manifolds leaks will make it run lean.

If the radiator in the car is flowing water good and air moving freely its not the radiator. Did you do a compression leak down test on the cylinders. Check for vacuum leaks at the intake. Add an Air/fuel gauge. Before and after pictures.

before

after

Never over heated with the race motor and factory radiator for a non AC car with AC installed. Most times over heating has nothing to do with the radiator. But many times people put a big radiator in to fix a problem that is caused by something else.

 

[Bewy]

Post #8.
Yes, copper has better thermal conductivity than alum; but the larger tubes that can be used with alum allows for much more efficient heat-shedding fin design, so the alum rad cools better.

 

[Demonic]

While it is true that copper is more thermally conductive vs aluminum, air-to-water heat exchangers are dominated by the air side effectiveness, which the aluminum fin is much more effective than copper.

Factory Mopar thermostats flow significantly more than the aftermarket standard. I suspect the run of the mill "Stant" or typical units are a Chevy/Ford design. If you see an actual 2128944/3514774 or 3514177, the opening diameter is about 7/16' larger. Run a high flow or factory thermostat.

 

[Bakerlite]

Copper tube is more effective at drawing the heat out of the coolant to begin with.
Look at HVAC , copper tube, alloy fin for the standard version. Copper tube and fin for the more expensive. A lot of it just comes down to cost.

Here is a quote from a HVAC manufacturer .
"It’s really not a coincidence why HVAC coils use copper tubes and aluminum fins. Copper is great for heat transfer, and aluminum – while still very effective -is simply not as good. The first goal of any HVAC coil is to cool or heat. Heat transfer is always the first consideration. Cost is the second. Copper works well for the tubes, but would be prohibitive for the fins. You would need a compelling reason for the fins to be copper, and sometimes there are reasons to do just that. However, the vast majority of HVAC coils that you see are built with copper tubes and aluminum fins.. That combination offers the most effective heat transfer at the most efficient cost. "

Anyway....most go to an alloy radiator because they are cheap, not because they think it's a superior design , material or contains magic.

 

[Bakerlite]

Post #8.
Yes, copper has better thermal conductivity than alum; but the larger tubes that can be used with alum allows for much more efficient heat-shedding fin design, so the alum rad cools better.

Sounds like you could do all of that with copper as well. Bigger tubes, fin design..
You're beginning to sound like one of the American Cruising Inc crowd that used to hang around that service station on Mona Vale..

 

[Rat Bastid]

Yeah, it's not that simple. Not at all.

Your anecdotal evidence about "cars that overheat under yellow" gives 4 different variables, any ONE of which could be the source of their overheating issue. And for many of them, it probably isn't the radiator at all. Because here's the thing, cars that overheat when sitting still usually have a fan problem, not a radiator problem. If they're staying cool at speed their radiator is fine, they're not moving enough air through the radiator sitting still. And of course, using a race car example is usually a bad choice, because people do really specific things that work well for their type of racing that will not hold up for a street driven car anyway.

The problem is that none of the aftermarket radiator companies, or the factory ones for that matter, publish enough of their specs to do a full mathematical calculation on them. This is on purpose.

A radiator is just ONE part of the whole cooling system. The water pump, the pulley ratio's, the CFM of air the fans can flow, the rate of coolant circulation, horsepower of the engine, ALL of that matters. If you look at the factory cars you see Ma Mopar had two major configurations, AC and non-AC. The non-AC cars got a .95:1 water pump pulley ratio (technically under driven!) and the HD 8 vane water pump (and usually a 2 core radiator). The AC cars got a 1.3 or 1.4:1 water pump pulley ratio, the standard 6 vane water pump, and a 2 or 3 core radiator depending on the engine, year, model, etc. Why did they change the water pump? Wouldn't more water flow be better for the AC cars that needed more cooling? Well, they wanted to increase the air circulation and keep the water circulation closer to the same. Overdriving the water pump was to speed up the fan, to move more air. But they downgraded the water pump, to keep that rate similar as the other set up. Almost like there was an ideal water circulation rate for that system and pump.

It's a cooling system, and you can't have a "properly engineered" radiator unless it was engineered specifically for all of the specifications of that particular car. Since we don't have unlimited ability to select pulley ratios, water pump output volumes, fan CFM etc there's gonna be a limit to what works well. And the "biggest two core radiator" that will fit isn't the only answer. Or even necessarily the right answer.

I run a 3 core with Ford Contour electric fans. Has worked great for me, even stuck in traffic in 110°F weather. I wouldn't trade it for a 2 core just because someone says bigger tubes are better.



Fan CFM has to be matched to the rest of the system. If you replace a mechanical fan that has an output of 4,500 cfm with an electric fan, you're gonna need an electric fan that can pull 4,500 cfm or so if you want to have a decent chance at it working. It's not the fan stalling that's the issue, it's usually just a lack of output. People seem to have a habit of picking fans because they have a cool aftermarket name or cost a certain amount instead of picking them by the CFM they can move. There are plenty of really expensive aftermarket electric fans that don't move enough CFM for these cars.

I said all that. It’s that simple.

Let me lay it out again.

Biggest TWO CORE radiator that will fit. You can say more cores are better all you want, but not ONE performance radiator builder will tell you more smaller cores are better at cooling. Griffin told me they will build a three core because that’s what some guys want, but they won’t do it if they don’t have to.

Overdrive the pump. ALWAYS. That also gets the fan speed up.

High flow water pump.

High flow thermostat.

Correct tune up.

You do that and you’ll never have heating issues unless someone goes full on retard with something.

And just to end this bullshit argument, I’ll post these links from THE cooling EXPERTS. Everyone should read the links and think for themselves.

Tech Tip #1: Water Pumps & Pulleys - Stewart Components

https://www.stewartcomponents.com/tech-tips/tech-tip-3-thermostats-restrictors/

https://www.stewartcomponents.com/tech-tips/tech-tip-3-thermostats-restrictors/

https://www.stewartcomponents.com/tech-tips/tech-tip-5-radiators-external-plumbing/

https://www.stewartcomponents.com/tech-tips/advanced-cooling-system-basics/

There are more tech pages there but these should be enough that more cores, multiple pass radiators and junk like that aren’t what should be used.

 

[Bakerlite]

I said all that. It’s that simple.

Let me lay it out again.

Biggest TWO CORE radiator that will fit. You can say more cores are better all you want, but not ONE performance radiator builder will tell you more smaller cores are better at cooling. Griffin told me they will build a three core because that’s what some guys want, but they won’t do it if they don’t have to.

Overdrive the pump. ALWAYS. That also gets the fan speed up.

High flow water pump.

High flow thermostat.

Correct tune up.

You do that and you’ll never have heating issues unless someone goes full on retard with something.

And just to end this bullshit argument, I’ll post these links from THE cooling EXPERTS. Everyone should read the links and think for themselves.

Tech Tip #1: Water Pumps & Pulleys - Stewart Components

Tech Tip #3: Thermostats & Restrictors - Stewart Components

Tech Tip #3: Thermostats & Restrictors - Stewart Components

Tech Tip #5: Radiators & External Plumbing - Stewart Components

Advanced Cooling System Basics - Stewart Components

There are more tech pages there but these should be enough that more cores, multiple pass radiators and junk like that aren’t what should be used.

Yet here is a quote from Natrad, who have been building radiators for over 100 years and were suppliers of original equipment to , Holden, Ford and Kenworth.

" 1-2 row is ideal for stock standard vehicles and exact replacement requirements.
3-4 rows are best for high horsepower, performance or off-roading vehicles as well as trucks."

Picking your radiator core: 2 row, 3 row, or 4 row? -

Are you looking to replace a radiator? Well look no further because we have created an extensive guide for picking the ideal radiator choice for you!

natrad.com.au

Trucks, hmmmm...
Kenworth Truck Radiator

Fits: T600, T700, T800

W900 - with CAT C15 500HP Engine
Years: 1988 to 2007
4 Row, High Efficiency Core w/ Bolted-on Tanks
Includes Surge Tank; Inlet Connection is Curved

From personal experiences, I've never had heating issues using more than 2 cores in a radiator. In fact, I've sometimes found benefits going to more cores.
Guess I'm just lucky.
One thing is for sure, maximize the surface area of the radiator.

 

[Rat Bastid]

Yet here is a quote from Natrad, who have been building radiators for over 100 years and were suppliers of original equipment to , Holden, Ford and Kenworth.

" 1-2 row is ideal for stock standard vehicles and exact replacement requirements.
3-4 rows are best for high horsepower, performance or off-roading vehicles as well as trucks."

http://[URL]https://natrad.com.au/info-advice/picking-your-radiator-core-2-row-3-row-or-4-row/

[/URL]

Trucks, hmmmm...
Kenworth Truck Radiator

Fits: T600, T700, T800

W900 - with CAT C15 500HP Engine
Years: 1988 to 2007
4 Row, High Efficiency Core w/ Bolted-on Tanks
Includes Surge Tank; Inlet Connection is Curved

From personal experiences, I've never had heating issues using more than 2 cores in a radiator. In fact, I've sometimes found benefits going to more cores.
Guess I'm just lucky.
One thing is for sure, maximize the surface area of the radiator

Did you read the links? I’m not building tractor **** or HVAC.

 

[Bewy]

Radiators:
'Alum on the other hand is much stronger so the tubes can be twice as wide. At first glance this might not appear to be such an advantage...The water flow characteristics of a four row copper core are pretty much the same as a two row alum alum core. However, when we consider the heat transfer area the alum tubes EASILY wins to the tune of up to a 20% gain. The fins, which transfer heat to the air passing through the rad, only contact the flat sides of the tube. The rounded ends of the tubes have no finning, so there is no heat transfer of any significance from this area. Thus with only half the number of tube ends, the alum rad will give up more heat to the fins.'

From the Bosch Automotive Handbook, 9th Edition 1500+ pages.
' The cores of the coolant radiators in modern passenger cars are almost exclusively made of alum. ....There are two assembly variants: brazed & mechanically joined.
For HIGH PERFORMANCE engines, the best solution is the brazed flat tube & corrugated fin rad.'

 

[RustyRatRod]

Is this stupid phukkin arguing helping the OP ONE SINGLE BIT? No. So shut the hell up already.

 

[Bakerlite]

Did you read the links? I’m not building tractor **** or HVAC.

Tractors ( as in truck) can run at high loads at low speed, which generates lots of heat, so you would need an effective radiator and they make them in 4 core.
Point is, it's not real bright just to say that more than 2 cores are junk.

more cores, multiple pass radiators and junk like that aren’t what should be used.

 

[Bakerlite]

Radiators:easy
'Alum on the other hand is much stronger so the tubes can be twice as wide. At first glance this might not appear to be such an advantage...The water flow characteristics of a four row copper core are pretty much the same as a two row alum alum core. However, when we consider the heat transfer area the alum tubes EASILY wins to the tune of up to a 20% gain. The fins, which transfer heat to the air passing through the rad, only contact the flat sides of the tube. The rounded ends of the tubes have no finning, so there is no heat transfer of any significance from this area. Thus with only half the number of tube ends, the alum rad will give up more heat to the fins.'

From the Bosch Automotive Handbook, 9th Edition 1500+ pages.
' The cores of the coolant radiators in modern passenger cars are almost exclusively made of alum. ....There are two assembly variants: brazed & mechanically joined.
For HIGH PERFORMANCE engines, the best solution is the brazed flat tube & corrugated fin rad.'

Go look at the construction of some of the alloy radiators on the market today. You'd probably be better off attaching radiator hoses to that Bosch book you have .lol.
Anyway...
Back in the day, no one seemed to have cooling issues with iron heads, big cams, decent comp, stock water pumps, stock pulleys and crappy tune ups. All through crappy old copper radiators.
I use Alloy radiators ,they can be cost effective, I don't have an issue with them, unless a tube gets damaged, then it's not as easy to repair as copper.
Want to see one with more than 2 cores?

P51 Mustang, no cooling issues there !!

 

[Rat Bastid]

Is this stupid phukkin arguing helping the OP ONE SINGLE BIT? No. So shut the hell up already.

Hopefully someone reads the links and learns something. I doubt it though because the tractor and HVAC crowd can’t get through their head that restriction to flow is BAD. Doesn’t matter if it’s air or coolant flow.

Some people can’t learn because they think that one factor is all that counts.

I say it’s a system and it gets argued. Typical ****. Then they say exactly what I said.

So more than two cores is just marketing bullshit and multi pass radiators are straight garbage.

You can’t double the restriction and not have issues. And that’s what a 2 pass radiator does.

It’s pretty simple really.

And, most of these guys think if their **** stays under 200 with a 190 or worse yet a 180 thermostat they are golden. Nothing could be farther from the truth.

Stewart Components explained this very well in one of the links I posted.

 

[RustyRatRod]

Hopefully someone reads the links and learns something. I doubt it though because the tractor and HVAC crowd can’t get through their head that restriction to flow is BAD. Doesn’t matter if it’s air or coolant flow.

Some people can’t learn because they think that one factor is all that counts.

I say it’s a system and it gets argued. Typical ****. Then they say exactly what I said.

So more than two cores is just marketing bullshit and multi pass radiators are straight garbage.

You can’t double the restriction and not have issues. And that’s what a 2 pass radiator does.

It’s pretty simple really.

And, most of these guys think if their **** stays under 200 with a 190 or worse yet a 180 thermostat they are golden. Nothing could be farther from the truth.

Stewart Components explained this very well in one of the links I posted.

Makes zero sense to compare tractors to our cars. Most tractors travel at speeds well under 20 MPH, so what good does air flow do? Their radiators are a different design.

 

[Rat Bastid]

Makes zero sense to compare tractors to our cars. Most tractors travel at speeds well under 20 MPH, so what good does air flow do? Their radiators are a different design.

LOL, you know that as a farm boy. I know that because I worked on farms. Others may not know that.

 

[RustyRatRod]

LOL, you know that as a farm boy. I know that because I worked on farms. Others may not know that.

My 49 Ford 8N has a top speed of 12 whole MPH. lol

 

[Bakerlite]

Makes zero sense to compare tractors to our cars. Most tractors travel at speeds well under 20 MPH, so what good does air flow do? Their radiators are a different design.

I mentioned trucks...not farm tractors... geez louise. Having said that, the
Fiat farm tractor I use to slash, has a conventional copper car style radiator in it.
Jimbo's farther Rocky used to call trucks " tractors" he was a gear jammer!
But on the subject of trucks, notice where the temp sender is on a smallblock truck engine?

 

[Bakerlite]

Hopefully someone reads the links and learns something. I doubt it though because the tractor and HVAC crowd can’t get through their head that restriction to flow is BAD. Doesn’t matter if it’s air or coolant flow.

Some people can’t learn because they think that one factor is all that counts.

I say it’s a system and it gets argued. Typical ****. Then they say exactly what I said.

So more than two cores is just marketing bullshit and multi pass radiators are straight garbage.

You can’t double the restriction and not have issues. And that’s what a 2 pass radiator does.

It’s pretty simple really.

And, most of these guys think if their **** stays under 200 with a 190 or worse yet a 180 thermostat they are golden. Nothing could be farther from the truth.

Stewart Components explained this very well in one of the links I posted.

The HVAC was simply showing how different metals can be combined in a heat exchanging device.
And you're the one who first said tractor.
Don't bring me into another of your " everyone's an idiot" ritalin rants.
You've posted links to someone elses work, now get back in your hole, or nest, or wherever a Rat resides.

 

[Rat Bastid]

The HVAC was simply showing how different metals can be combined in a heat exchanging device.
And you're the one who first said tractor.
Don't bring me into another of your " everyone's an idiot" ritalin rants.
You've posted links to someone elses work, now get back in your hole, or nest, or wherever a Rat resides.

Like always, you bring in a bunch on nonsense and bullshit and then claim the high ground.

I posted links to what the experts say rather than listen to a down under fool with a big mouth.

 

[Bakerlite]

How unlike you to get triggered, over nothing.

 

[Oldmanmopar]

I think you can hook the upper and lower hose together and head across country. Radiators are not needed if you have a big fan. keep it under 55. LMFAO

 

[RustyRatRod]

I think you can hook the upper and lower hose together and head across country. Radiators are not needed if you have a big fan. keep it under 55. LMFAO



View attachment 1716056667

That fish picture is hilarious. lol

 

[jdsduster]

i have a 408 stroker ,it has a 26" cold case radiator.it cools great in 100 deg.weather.never goes over 180 deg.stopped or moving,it has 2 rows