Radiator

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Bigdummy

Bigdummy

Not a Nova
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Well my 69 Valiant is getting hot,so I'm starting to look at some radiators,the one I have is a 2 row aluminum 24x18 and ive been looking at a 27x19 .When I first got the car it had a electric pump on it so I put a belt driven on it with a fan it helped but still getting hot.A fan shroud would help but a bigger Radiator and a shroud should do it!I wanna add Vintage air...Its hot in Texas



 
I dont no how hot or when your getting hot but a real fan 5-7 blade and schroud would do miracles as long as your not clogged, also what thermostat are you running 180-185?
 
Wow....that engine bay looks awesome! :prayer: Agreed on the shroud, and more cores definitely won't hurt.
 
My 383 70 RR used to run hot with the stock radiator. There was no fan shroud, so I added one. Didn't make a lick of difference. Bought a new Champion Aluminum rad 3-row which is actually smaller length and height-wise. No mounting brackets for the shroud so I left it off. The car used to run about 200-210 degrees, but now hasn't run over 180* - with no shroud.

Yeah, a 3-row rad will make a difference, but the primary objective of the shroud is to keep objects away from the fan, not aid air flow.
 
caveman85635 said:
Yeah, a 3-row rad will make a difference, but the primary objective of the shroud is to keep objects away from the fan, not aid air flow.
Click to expand...

That is 100% wrong.

In your example you probably had a capacity issue, where increasing the capacity helped.

More often (and we have had hundreds of threads on cooling issues), it's an airflow issue.

People start deleting parts of their cooling system and run into trouble.

The shroud, a correctly sized fan, the thermostat, the rubber hood seals, they are all part of a correctly functioning cooling system.
 
I have a 160 degree thermostat but am going to a 180 when i get a bigger radiator and a fan shroud.I plan on Vintage air
 
Bigdummy said:
I have a 160 degree thermostat but am going to a 180 when i get a bigger radiator and a fan shroud.I plan on Vintage air
Click to expand...

So, um..... Lets say your car is at 205 degrees.

Your 160 stat is open, right?

Oh, and if you had a 180 stat, it would be open too, right?

So what's that 160 stat doing for you?


That's right...... Absolutely nothing.


Why do so many of you continue to think that a stat opening early helps?


After 20 minutes your engine doesn't know or care if your 160 stat opened 4 minutes before a 180 would have.


Your car runs hot because you have removed part of the cooling system and replaced other parts with crap, like that fan.
 
I suspect the fan he has is all that will fit in the modified engine bay. I had to use a similar-looking nylon fan in my 65 Dart after switching my SB to the longer alum water pump.

I have a very similar-looking alum radiator in my 65 Newport 383. I used a shroud I had from a ~80 New Yorker SB, which fits well, so look for one at the junkyard. I had to trim it a little around the tubes. I made 4 straps to mount it from the upper and lower rail holes. Can't comment on the cooling since I haven't had that car insured since the mod.
 
I'll try the shroud and 180 thermostat first.I might add the air next year.Thanks for everyone's input
 
My brother has a 526 hemi runs 2 electric fans and the only time they have to work is in town when he hits a couple red lights. Get the right combo and you will be fine, also when does it get hot in town or out on the highway that will tell the story as to what you need.
 
1968FormulaS340 said:
So, um..... Lets say your car is at 205 degrees.

Your 160 stat is open, right?

Oh, and if you had a 180 stat, it would be open too, right?

So what's that 160 stat doing for you?


That's right...... Absolutely nothing.


Why do so many of you continue to think that a stat opening early helps?


After 20 minutes your engine doesn't know or care if your 160 stat opened 4 minutes before a 180 would have.


Your car runs hot because you have removed part of the cooling system and replaced other parts with crap, like that fan.
Click to expand...

Maybe in this particular case a lower t-stat won't give the desired result, but in a car with the proper cooling capacity(large enough radiator, adequate air flow, no blockage) a lower temp t-stat will reduce engine temperature. Keep in mind it's not just the temp it opens at, but also when it closes again. A lower t-stat will allow cooled coolant to flow into the engine longer. That will lower the temperature.
Many radiators sold & installed in performance cars don't have adequate cooling capacity. It's not just how much water it holds or external dimentions, but how much water it can effectively cool. A radiator can hold more water in it but not have enough passeges in the cores or enough fins(or large enough fins) to efficeintly cool the system down. People used to run into trouble when they would paint the fins of their radiator & while it looked nice & shiney, it couldn't cool effectively anymore because the painted fins couldn't disipate the heat enough. The cooling capacity was reduced.
As for fan shrouds, they serve a dual purpose. They do protect from objects(hands, feet, tools, neck ties, etc) but they also direct more air flow through the radiator as well. Kinda like being smart & sexy!
 
If schrouds were only on there for protection all cars would have them, there mostly for cooling better at low speed.
 
1968FormulaS340 said:
That is 100% wrong.

In your example you probably had a capacity issue, where increasing the capacity helped.

More often (and we have had hundreds of threads on cooling issues), it's an airflow issue.

People start deleting parts of their cooling system and run into trouble.

The shroud, a correctly sized fan, the thermostat, the rubber hood seals, they are all part of a correctly functioning cooling system.
Click to expand...

Sorry, FormulaS340, but I am not 100% wrong. As a designer, engineer, and supervisor, I've spent the last 30 years of my life designing/engineering engine compartment components for all of the original Big Three auto companies. I did sheet metal parts as well as plastic parts. I've done at least a half dozen fan shrouds during my career, and I'm hear to tell you that cooling is not and was not the primary objective of fan shrouds. The primary objective, according to the project goals, is protection from a running fan. Then, IF there was room to package it, I would make the shrouds as efficient as possible to aid airflow. Packaging room under the hood can be difficult to find on today's new cars. After the shroud was designed, a prototype would be mocked up, bolted onto a vehicle, and then tested for efficiency. They always worked at an acceptable level of efficiency. As a car guy, it irritated me that cooling efficiency was not the primary objective of fan shroud design.
One of the problems we discovered is that there were 'hotspots' on the radiator with the fan shroud installed. The hotspots were in all four corners of the rad where the shroud was close to the core, because the fan opening is round, and the shroud was square or rectangular. Testing without the shroud revealed that there were no hotspots, but there was no significant increase, or decrease, in cooling efficiency.
One of the coolest (no pun intended) jobs I did was on the '86 IROC/Z28/RS Camaro's. The '85's cooling system was the lamest I had ever seen, with or without a shroud. It turned out the front spoiler would bend toward the road surface at high speeds, due to not enough support, and block most of the incoming air, causing the car to run hot. I was assigned the task of fixing the problem. I designed an air ducting system that was superior to the existing system, even though all they wanted was a couple of braces to keep the spoiler from drooping. Since I had an '85 with the cooling problems, I wanted to design a system that would work well, and be able to be retrofitted to the '85's. I received a plaque and a patent for the design.
I don't disagree with anything else you say. I would much rather have a fan shroud than not, for sure. As you say, I am certain the extra capacity of the radiator was the major contributor to solving my cooling problems.
 
caveman85635 said:
Sorry, FormulaS340, but I am not 100% wrong. As a designer, engineer, and supervisor, I've spent the last 30 years of my life designing/engineering engine compartment components for all of the original Big Three auto companies. I did sheet metal parts as well as plastic parts. I've done at least a half dozen fan shrouds during my career, and I'm hear to tell you that cooling is not and was not the primary objective of fan shrouds. The primary objective, according to the project goals, is protection from a running fan. Then, IF there was room to package it, I would make the shrouds as efficient as possible to aid airflow. Packaging room under the hood can be difficult to find on today's new cars. After the shroud was designed, a prototype would be mocked up, bolted onto a vehicle, and then tested for efficiency. They always worked at an acceptable level of efficiency. As a car guy, it irritated me that cooling efficiency was not the primary objective of fan shroud design.
One of the problems we discovered is that there were 'hotspots' on the radiator with the fan shroud installed. The hotspots were in all four corners of the rad where the shroud was close to the core, because the fan opening is round, and the shroud was square or rectangular. Testing without the shroud revealed that there were no hotspots, but there was no significant increase, or decrease, in cooling efficiency.
One of the coolest (no pun intended) jobs I did was on the '86 IROC/Z28/RS Camaro's. The '85's cooling system was the lamest I had ever seen, with or without a shroud. It turned out the front spoiler would bend toward the road surface at high speeds, due to not enough support, and block most of the incoming air, causing the car to run hot. I was assigned the task of fixing the problem. I designed an air ducting system that was superior to the existing system, even though all they wanted was a couple of braces to keep the spoiler from drooping. Since I had an '85 with the cooling problems, I wanted to design a system that would work well, and be able to be retrofitted to the '85's. I received a plaque and a patent for the design.
I don't disagree with anything else you say. I would much rather have a fan shroud than not, for sure. As you say, I am certain the extra capacity of the radiator was the major contributor to solving my cooling problems.
Click to expand...

Cool story Bro. But you are still wrong. Try idling an early 70s Monty Carlo without a shroud and see where that gets you.

Modern cars use more front side ducting and and a closer fan to radiator position, more often than not, that fan is electric. (I deal with this stuff everyday).

Your example is really apples and oranges. We are dealing with 60s and early 70s design philosophy here.
 
Lonewolf3165 said:
Keep in mind it's not just the temp it opens at, but also when it closes again. A lower t-stat will allow cooled coolant to flow into the engine longer. That will lower the temperature.
Click to expand...
I don't think the thermostat opens and closes as you drive. That would be like the furnace control in your home. Instead it is a "proportional controller", which reaches a steady-state operating condition, i.e. partially open and not cycling. I think 1968FormulaS340 is correct. If you are over-heating with a 180 F thermostat, your thermostat is already fully open, i.e. beyond the proportional control range or "control response pegged out". A 160 F thermostat would also be full open there, so where is the benefit? The downside would be that a 160 F thermostat could make your engine run too cool in the winter, with poorer mileage, more emissions, and more cylinder wear. Poorer temperature control is why air-cooled engines like old VW's need a rebuild more often than liquid-cooled.
 
caveman85635 said:
Sorry, FormulaS340, but I am not 100% wrong. As a designer, engineer, and supervisor, I've spent the last 30 years of my life designing/engineering engine compartment components for all of the original Big Three auto companies. I did sheet metal parts as well as plastic parts. I've done at least a half dozen fan shrouds during my career, and I'm hear to tell you that cooling is not and was not the primary objective of fan shrouds. The primary objective, according to the project goals, is protection from a running fan. Then, IF there was room to package it, I would make the shrouds as efficient as possible to aid airflow. Packaging room under the hood can be difficult to find on today's new cars. After the shroud was designed, a prototype would be mocked up, bolted onto a vehicle, and then tested for efficiency. They always worked at an acceptable level of efficiency. As a car guy, it irritated me that cooling efficiency was not the primary objective of fan shroud design.
One of the problems we discovered is that there were 'hotspots' on the radiator with the fan shroud installed. The hotspots were in all four corners of the rad where the shroud was close to the core, because the fan opening is round, and the shroud was square or rectangular. Testing without the shroud revealed that there were no hotspots, but there was no significant increase, or decrease, in cooling efficiency.
One of the coolest (no pun intended) jobs I did was on the '86 IROC/Z28/RS Camaro's. The '85's cooling system was the lamest I had ever seen, with or without a shroud. It turned out the front spoiler would bend toward the road surface at high speeds, due to not enough support, and block most of the incoming air, causing the car to run hot. I was assigned the task of fixing the problem. I designed an air ducting system that was superior to the existing system, even though all they wanted was a couple of braces to keep the spoiler from drooping. Since I had an '85 with the cooling problems, I wanted to design a system that would work well, and be able to be retrofitted to the '85's. I received a plaque and a patent for the design.
I don't disagree with anything else you say. I would much rather have a fan shroud than not, for sure. As you say, I am certain the extra capacity of the radiator was the major contributor to solving my cooling problems.
Click to expand...

So a fan shroud being part of the factory a/c package is to keep what out of the fan ?
 
Caveman...what you say makes sense,the fan will move the same amount of air regardless of where it pulls from.If it misses the corners then it will cool the center more..just physics!
..and with a 160 degree thermostat your engine will take longer to warm up..not good because that's where most of the wear occurs.
 
1968FormulaS340 said:
Cool story Bro. But you are still wrong. Try idling an early 70s Monty Carlo without a shroud and see where that gets you.

Modern cars use more front side ducting and and a closer fan to radiator position, more often than not, that fan is electric. (I deal with this stuff everyday).

Your example is really apples and oranges. We are dealing with 60s and early 70s design philosophy here.
Click to expand...

I didn't say I
, or the design objectives, were entirely correct. Just relating my experiences.

Yes, the design philosophies have changed over the years. These days, the bottom line is packaging. Back when we had tons of space under the hood, packaging was no problem. Today, packaging space is a premium, and packaging is the name of the game.
 
ir3333 said:
Caveman...what you say makes sense,the fan will move the same amount of air regardless of where it pulls from.If it misses the corners then it will cool the center more..just physics!
..and with a 160 degree thermostat your engine will take longer to warm up..not good because that's where most of the wear occurs.
Click to expand...

I am very close to changing to a 180 degree thermostat just for quicker warm ups. It takes too long for me to warm up with a 160.
 
RedFish said:
So a fan shroud being part of the factory a/c package is to keep what out of the fan ?
Click to expand...

Finger, hands, clothing, tools, rags, small animals, little children, etc...

Have you ever noticed, on the top side of the shroud, there is either a label or a warning molded into the plastic that says, "Caution fan". It doesn't say, "Caution airflow". In the business, the shroud was regularly referred to as the 'Caution fan' because that's what it said on it LOL
 
1968FormulaS340 said:
Cool story Bro. But you are still wrong. Try idling an early 70s Monty Carlo without a shroud and see where that gets you.

Modern cars use more front side ducting and and a closer fan to radiator position, more often than not, that fan is electric. (I deal with this stuff everyday).

Your example is really apples and oranges. We are dealing with 60s and early 70s design philosophy here.
Click to expand...

I'm glad you think it's a cool story, 340, but it's fact. I have seen enough testing of shrouds and cooling systems, and identifying hotspots over the years, to know what I'm saying is TRUE. I believe the design objectives were wrong, and always tried to create the best airflow possible with what I had to deal with. Hence my greatest cooling design achievement on the '86 and up Camaro's. Vehicles equipped with A/C pose many more issues, as opposed to those without A/C. Now that is the apples and oranges. Many more issues with A/C, understandably so.
 
caveman85635 said:
Finger, hands, clothing, tools, rags, small animals, little children, etc...

Have you ever noticed, on the top side of the shroud, there is either a label or a warning molded into the plastic that says, "Caution fan". It doesn't say, "Caution airflow". In the business, the shroud was regularly referred to as the 'Caution fan' because that's what it said on it LOL
Click to expand...

Wrong again, The warning flag wasn't added until 1970. Reason being, the shroud blocks the view of the fan.
A shrouds original purpose was to direct more airflow through the radiator. That's why it was part of a/c and or performance packages.
I do know better than to argue in a public forum though, especially with an engineer. Good luck to all
 
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