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Discussion Starter #1
My Question is whether a Custom Built Radiator will work better than a out of the box AFCO or Griffin aluminum radiator?


I presently have a Walker 4 Row Cobra Z-Series copper/brass specially designed for my Car. 34 Ford replica with BB Chevy and AC.


The car runs down the road very cool, even with bursts through the gears will stay around 180. But will creep up to 200 and over if its sitting still at idle.


The motor only has a couple hundred miles on it and I haven't completed the hood yet. I live in south Florida so I am anticipating Summer days with AC on and a Full hood that I will be running into problems.


Its a ZZ502 crate motor from chevy dealer w front serpentine package, carburation and ignition assembled from the factory as a deluxe package.


just looking for feedback from other owners with aluminum radiators. Thanks to all in advance.
 

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My Question is whether a Custom Built Radiator will work better than a out of the box AFCO or Griffin aluminum radiator?


I presently have a Walker 4 Row Cobra Z-Series copper/brass specially designed for my Car. 34 Ford replica with BB Chevy and AC.


The car runs down the road very cool, even with bursts through the gears will stay around 180. But will creep up to 200 and over if its sitting still at idle.


The motor only has a couple hundred miles on it and I haven't completed the hood yet. I live in south Florida so I am anticipating Summer days with AC on and a Full hood that I will be running into problems.


Its a ZZ502 crate motor from chevy dealer w front serpentine package, carburation and ignition assembled from the factory as a deluxe package.


just looking for feedback from other owners with aluminum radiators. Thanks to all in advance.
Temperature creep at idle is an air flow problem. Typical customs retro builds use a fan in the center between the radiator and engine, this leaves a lot of fin area outside the fan circle doing little to nothing till the vehicle is moving which pushes are into these otherwise static areas of the core. The answer is really a shroud between the radiator and puller fan but nice looking shrouds for these just are not available.

My experience has found that an aluminum radiator is no more effective at cooling than copper/brass units, they are just lighter which is nice but doesn't solve any cooling issues.

A solution to your problem can be found at these links:

Fan Shroud Fabrication - Hot Rod Network

Fabricating a 1932 Ford Fan Shroud - Hot Rod Network

Bogie
 

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RedLine Stage 4 ZL1 650rwhp
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ya what he said a proper Shroud is a must.
You didn't mention what Fan / Fans your using, what are you using Realtor ?

AS for will a custom radiator work better.... All I know from personal experience is I've had great luck with 2 Row 1" Tube Radiators over 4 Row 1/2 Tube Radiators.
 

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Discussion Starter #4
fan shroud

There was no room between engine and radiator for a fan. I have 2 electric pusher fans mounted on the condenser. 13 inch on top and 11 inch underneath. In the shop with both fans running and 2 Stanley Barrel style carpenter fans pointed at the radiator it will creep up to 220. There is a 21lb radiator cap and a gutted thermostat,


Ideas?
 

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If your pushers are mounted on the condenser you are probably having a lot of losses from between your condenser and radiator. In most cases pushers block air flow while the car is moving but this does not seem to be your problem.
My recommendation would be to make a shroud in front of the radiator that encases the condenser and makes sure all of the flow is passing through your radiator. And put the biggest pushers you can on it. They tend to run about 20% less efficient.

I agree with the other posters, you have enough radiator, you have air flow issues while the car is not moving. If you have access to a shear and brake you could fabricate an aluminum shroud very easily.

Good luck, sounds like a monster machine!
 

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Sorry to double post, I just saw some pictures of your car and it is a beauty.
I also noticed on the front view that your lower pusher has an open spot below it and you have a lot of room for air to bypass the radiator.
Between the pusher config and the open space you are just not pumping enough air through the radiator. Seal it up and you will have your problem solved.
 

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I am not a fan of running a gutted thermostat on the street. If you're running a racing water pump coined as even flow. Then they block off the bypass passage in the pump and you have to gut the thermostat or run water restrictors. Otherwise, gutting the thermostat makes the engine run too cold most of the time, which builds up moisture and other deposits in your oil. A thermostat slows the water flow through the radiator and gives it time to cool off. Besides helping with idle quality, it helps your heater put out warm air, if you have one.

The best solution is a mechanical fan with a shroud as stated above. Having the hood on will change the whole dynamic, for better or worse. Seal that gap between the fan and condenser, and the condenser and the radiator first. I have had to pull the electric fans and go mechanical with some big block applications which were overheating at idle.

Do your engine a favor and replace that thermostat. Gutting it is not helping your idle overheat problem and will decrease engine longetivity.

Sent from my XT1096 using Tapatalk
 

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I am not a fan of running a gutted thermostat on the street.

Sent from my XT1096 using Tapatalk
I second this emotion. Gutted t-stats and restrictors work for race cars that spend extended periods in a certain rpm range and have the pulleys setup to control flow volumes to keep the coolant in the radiator long enough to cool off. On the street they stink.

You might need a high flow t-stat or just a standard one, test it out and see what happens. But other than that, I would not be concerned about coolant creep to 200 degrees from 180 when sitting idling. But that's me.
 

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RedLine Stage 4 ZL1 650rwhp
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There was no room between engine and radiator for a fan. I have 2 electric pusher fans mounted on the condenser. 13 inch on top and 11 inch underneath. In the shop with both fans running and 2 Stanley Barrel style carpenter fans pointed at the radiator it will creep up to 220. There is a 21lb radiator cap and a gutted thermostat,

Ideas?
What a beautiful machine :thumbup:

Thats a unique set up you have and with the fans on the condenser it probably is hurting you. When you say you have no room between engine and radiator how much room do you have ? There are fans out there that are only 2" depth, and a lot of fans the same diameter have very different CFM's, do you know the CFM's for your fans ?

EXAMPLE

Hard to tell from the pic but it looks like you could go a little larger on both fans, could you ??? It's all about the CFM's....
 

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Discussion Starter #10
Fans , Thermostats & Shrouds

Guys, a lot of good ideas, I appreciate all of it. I only have an inch between the motor and the radiator so I cant go to the mechanical fan. But I did have second thoughts about the thermostat so I will go back to a complete stat. Also I understand what you are saying about closing up the holes on the front side and under the radiator to make a shroud so the fans will pull more air through the radiator. I should have spotted that myself, I had a Sunbeam Tiger years ago and when I put a Boss 302 motor in it I had to make air scoops and shrouds. When I have it apart I am going to look into the bigger fan vs the 2 I have on there now. I'm basically building this on my own so this forum is the only group I have to reach out to for second opinions. most of the guys in this area have store bought factory muscle cars new and old. I wanted something different, its a bit more work, but worth it. Thanks for your help!
 

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There was no room between engine and radiator for a fan. I have 2 electric pusher fans mounted on the condenser. 13 inch on top and 11 inch underneath. In the shop with both fans running and 2 Stanley Barrel style carpenter fans pointed at the radiator it will creep up to 220. There is a 21lb radiator cap and a gutted thermostat,


Ideas?
Pusher fans never work well they build a pressure between themselves and the core face where what can't get through the core either just stalls or if the area is open just bleeds around.

AC condensers just make a difficult situation worse by adding more resistance to airflow through the cores.

The BS surrounding electric fans is legion the advertising is free flow CFM which has nothing to do with pumping air through a restriction like a radiator core. Nothing is as effective as an engine driven fan inside a shroud pulling air through a core, next best is an electric mounted the same way.

Gutting a thermostat does nothing but slow the warm up cycle which where you are is probably a moot point because the ambient is warm to hot all the year round.

Given the space constraints there isn't much to be done. Remote coolers with fans can be added to the cooling system, as engine and transmission coolers in remote places where space can be found. Loops of large diameter copper pipe can be secured to the frame to increase the amount of coolant capacity and use the frame as a heat sink.

So there are tricks that can be used when there is no engine compartment or front end space but there is no magic elixir of different radiator materials or electric fans beyond what I describe. Taking the AC out would help but probably not a desireable option.

In real terms 220 is not crazy hot, edgy to be sure, but if controlled it is OK. The super high pressure on the system is dangerous and hard on parts. I'd consider Evans waterless coolant and lower system pressure at 12 to 16 psi.

Bogie
 

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Discussion Starter #12
Increase capacity

I took the car back from the builder, so basically I am rebuilding. I mentioned the cap rating because it also concerned me, Walker calls for a 15lb cap. Thanks for the feedback there. I was also thinking of the capacity, this system is so basic it holds a minimum amount of water. I am using the Royal Purple also. I may look for a way to increase capacity somehow. I would like to do it without loosing the heater if possible?
 

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An external transmission cooler (stacked plate type) won't add a tremendous amount to the fluid capacity of the system, but it may help to a certain degree by taking the brunt of the transmission cooling duties away from the small cooler in your radiator, thereby making your radiator more efficient. Also, are your headers coated with a thermal barrier? This may help to a small degree as well. Do you run a modern ATF in your trans? A properly fitting shroud is most important though.

Again, we aren't going to find a magic bullet, but if we can find 3 degree temperature drop in 3 or 4 places...thats enough to go from the nervous 220* zone to 210*

The higher pressure cap won't make it cool any better, just raise the boiling point of the fluid. So great it won't boil over till 260 degrees....by then you've got other problems.
 

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Discussion Starter #14
Trans cooler

I have a manual trans, 6 speed Tremec. I'm going to work on shrouding with a single large fan and some of the other suggestions made to start with. The headers are ceramic. I hear you , anywhere I can drop a few degrees will help in a traffic jam, I hate turning on the heater in 90 degree weather!
 

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Do you run the car with the 3-pc hood off completely, or maybe the sides open and just the top on?
Im assuming the pancake aircleaner is to be able to run a hood? Make sure you replace the element often as there isnt a lot of filter media there. I wonder if running with the sides open would help?
 

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Discussion Starter #16
Hood for 34

Right now I'm running no hood at all. I have a hood and side covers with upper and lower long rectangular cutouts running front to rear. Upper is approx. 2.5inch by 24 and lower about 2.5 x 14. Installing these is an upcoming project. I have just finished the interior work while sorting out the suspension, brakes clutch and motor, so the hood with new braces is next. But I wanted to decide on what to do with the radiator so I can do it all at once hopefully. I'm anticipating when I put the 3 hood pieces on I will build more heat. But I could also run it without the sides and pop them in when I get where I'm going.
 

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Discussion Starter #17
new motor

Also the motor only has 200 miles on it, if it makes a difference when it breaks in. Not sure if these crate motors are blueprinted to race specs or street specs.
 

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Race it, Don't rice it!
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My Question is whether a Custom Built Radiator will work better than a out of the box AFCO or Griffin aluminum radiator?

The radiator doesn't care about brand names but aluminum is lighter and generally better at conducting heat. Generally speaking, the name brands aer designed better. Fin count, tube size, tank thickness, better welds etc....


I presently have a Walker 4 Row Cobra Z-Series copper/brass specially designed for my Car. 34 Ford replica with BB Chevy and AC.


The car runs down the road very cool, even with bursts through the gears will stay around 180. But will creep up to 200 and over if its sitting still at idle.

I'd start to worry at 230. The higher pressure cap will keep the water in it longer. I'd rather it be hot and keep the water in it then lose water to a crappy cap. Caps are designed my engineers to blow off BEFORE a hose comes off or ballooning the radiator. If you have good hoses and a quality radiator, I would run the 30lb cap.


The motor only has a couple hundred miles on it and I haven't completed the hood yet. I live in south Florida so I am anticipating Summer days with AC on and a Full hood that I will be running into problems.


Its a ZZ502 crate motor from chevy dealer w front serpentine package, carburation and ignition assembled from the factory as a deluxe package.

I'd think about increasing the water pump speed as a good pump will move more water and create a turbulance for better cooling. I gotta feeling the water pump on there from GM is pretty crappy compared to a Stewart Pump.
Being a closed system the idea that water stays in the block too long also mean water stays in the radiator so ignore that. It's dumb.
Thermostats don't control your temp unless the system is way over designed so gutted, restricted, whatever, isn't really doing anything but creating more block pressure. Block pressure helps with cavitating and air bubbles in the water. A better pump fixes both.



One more thing. Controlling the oil temp takes a burden off the radiator so make sure your oil temps are in the ball park of 200'.
 

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[

Caps are designed by engineers to blow off BEFORE a hose comes off or ballooning the radiator.

The other purpose of a radiator cap is to purge air from the system. If the cap has too high of a relief pressure rating, then as the engine warms up and the water expands the air trapped at the top of the radiator will compress instead of being relieved out to the purge tank. Too high of a radiator cap pressure traps air in the system.







I'd think about increasing the water pump speed as a good pump will move more water and create a turbulance for better cooling. I gotta feeling the water pump on there from GM is pretty crappy compared to a Stewart Pump.
Being a closed system the idea that water stays in the block too long also mean water stays in the radiator so ignore that. It's dumb.
Thermostats don't control your temp unless the system is way over designed so gutted, restricted, whatever, isn't really doing anything but creating more block pressure. Block pressure helps with cavitating and air bubbles in the water. A better pump fixes both.[/QUOTE]


Increaseing the water pump speed with a pulley change could help the temp's at an idle. I doubt the water pump is cavitating at an idle where this problem lies.

The cooling system needs to be engineered for a hot day @ WOT. The engine needs a thermostat to control temperatures at less than WOT and on cold days. This also gets the oil temp up where it needs to be. This is a street car, not a dedicated track car running flat out all the time.

Years ago, I went on a trip with a car with a marginal radiator. Everything was fine until we took the drive through. While idling the temp got up to where the thermostat was wide open. Jumped back on the freeway and it would not cool back down. Stopped and put water on the radiator to cool it down, back on the freeway and the temp was stable. Hours later the Wife made me stop so she could change seats. While idling at an off ramp, the temp climbed some, pulled back on the freeway and the temp kept slowly climbing.
In a few miles I had to stop to water it down again. Once that thermostat was restricting water flow it would maintain it's temp on the freeway.

I don't see how a thermostat can build up pressure in the block. If the system is a closed pressurised tank, how can part of that system be at a higher pressure than the rest?
I believe that the thermostat slowed the water down so that the system could more efficiently shed heat, I could be wrong, I have been wrong before, but I believe that thermostats are an integral necessary part of the system.

People will pull the thermostat on their boat engine. Go fast and it runs cold, stop quickly and open the engine compartment, you will hear the engine crackling inside. So, based on my practical experience, I prefer to run thermostats.

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People will pull the thermostat on their boat engine. Go fast and it runs cold, stop quickly and open the engine compartment, you will hear the engine crackling inside. Sent from my XT1096 using Tapatalk
What is the cause of the 'crackling noise'? I've assumed it was exhaust expanding and contracting.
 
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