I don't think it would hurt anything HudginJ3.  I put high flow water pumps in the same category as high volume oil pumps.  Basically they are solutions in search of a problem.  You can't have enough water flow, right?  You can't have too much oil supply, right?  As it turns you, the answer is wrong on both counts. 

What you are describing is an issue with the coolant not being able to properly rid itself of heat.  If the radiator and fan package are up to the task I have to conclude that the fluid is simply not spending enough time in the radiator to get rid of the heat, and that's an issue with too much coolant flow.

I've run standard volume water pumps on pretty much everything I've ever built and never had an overheating issue that wasn't ultimately solved by something other than a high flow water pump. 

TKOPerformance wrote:

I don't think it would hurt anything HudginJ3.  I put high flow water pumps in the same category as high volume oil pumps.  Basically they are solutions in search of a problem.  You can't have enough water flow, right?  You can't have too much oil supply, right?  As it turns you, the answer is wrong on both counts. 

What you are describing is an issue with the coolant not being able to properly rid itself of heat.  If the radiator and fan package are up to the task I have to conclude that the fluid is simply not spending enough time in the radiator to get rid of the heat, and that's an issue with too much coolant flow.

I've run standard volume water pumps on pretty much everything I've ever built and never had an overheating issue that wasn't ultimately solved by something other than a high flow water pump. 

 
The “too much flow to reject the heat as it goes through the radiator” is an old shade tree mechanic’s tale that is not true. Higher flow increases turbulence which increases heat transfer. There is a limit to how much the higher flow pump will increase flow due to the flow restriction caused by the thermostat. Since the thermostat is in the flow path as the coolant exits the block, any flow restriction by the thermostat raises the coolant pressure in the engine which is a good thing since the coolant can hold more heat without boiling the higher the pressure is. The radiator will transfer a certain amount of heat at a certain differential temperature. It really does not matter how many times the coolant has to flow through the radiator. Having said all that, a standard flow water pump is probably all that is needed on a street driven car. A bigger radiator never hurts. A fan shroud greatly increases air flow through the radiator.

Hornman wrote:

TKOPerformance wrote:

I don't think it would hurt anything HudginJ3.  I put high flow water pumps in the same category as high volume oil pumps.  Basically they are solutions in search of a problem.  You can't have enough water flow, right?  You can't have too much oil supply, right?  As it turns you, the answer is wrong on both counts. 

What you are describing is an issue with the coolant not being able to properly rid itself of heat.  If the radiator and fan package are up to the task I have to conclude that the fluid is simply not spending enough time in the radiator to get rid of the heat, and that's an issue with too much coolant flow.

I've run standard volume water pumps on pretty much everything I've ever built and never had an overheating issue that wasn't ultimately solved by something other than a high flow water pump. 

 
The “too much flow to reject the heat as it goes through the radiator” is an old shade tree mechanic’s tale that is not true. Higher flow increases turbulence which increases heat transfer. There is a limit to how much the higher flow pump will increase flow due to the flow restriction caused by the thermostat. Since the thermostat is in the flow path as the coolant exits the block, any flow restriction by the thermostat raises the coolant pressure in the engine which is a good thing since the coolant can hold more heat without boiling the higher the pressure is. The radiator will transfer a certain amount of heat at a certain differential temperature. It really does not matter how many times the coolant has to flow through the radiator. Having said all that, a standard flow water pump is probably all that is needed on a street driven car. A bigger radiator never hurts. A fan shroud greatly increases air flow through the radiator.

Popcorn time............
 

HudginJ3 wrote:

I did install a high pressure oil pump at the same time during the build. The pressure stays right on the H till it gets real hot, then it goes down just a small amount. When the engine cools down with the AC off the pressure goes back up. The radiator is a 4 core aluminum designed for the Boss 302 and up engines. I'm running the Ford Contour fans that are on any time the AC is on and comes on at 190 with a 190 thermostat. It seems like it is better with that then it was with the engine driven fan, that was a flex fan. I installed one of those radiator caps with the thermometer in it. It seems pretty acurate.

 
You mean WATER pump, right?!

If you keep coolant in the radiator longer to cool it down more you simultaneously keep coolant in the block heating it up more. Sounds like a wash, mostly. Are there advantages to higher flow pumps? I think so, reduction of hot spots probably. Forcing more water past places where coolant flow is restricted. Even MS reported a 5 degree reduction in temperature after adding a flow cooler pump. I think most of our collective cooling problems simply stem from decades old blocks full of scale, rust, blockages and rough passages that were once smooth.
So, bigger radiators and more functional fans and shrouds all around please!

Last edited by Muzz 66 (8/04/2019 4:50 PM)

When the Edelbrock pump on my 427 started to seep a little, I replaced it, and nothing else, with a flowkooler pump. My gauge read five degrees cooler from then on.
Not sure exactly why. Just got a positive result.

Yes, I agree they are same pump as the OReilly or Autozone pumps with just an impeller disc riveted on.

The switch from 13# to 16# radiator cap solved overheating issues for me.
I made the change when I had installed a new 3 row copper brass radiator.
Also installed an electric fan to run with ignition on only.
I let the 180 degree thermostat regulate the temperature for 289.
Ran stock cast iron replacement water pump.
Hey, it was my daily ( only) driver at the time.

Would the small Hayden (6x11) 676 rapid-cool plate and fin cooler work as an aux cooler on a stock 289/C4 remotely located say below the alt with a T stat pusher fan on top? going through the champion radiator too. 
I think the cooler is a good idea just dont want to block more of my radiator, I have AC 

Overheating problems start in the engine itself.  You will eventually have to fix the actual problem. Bandaid fixes are temporary, at best, and cost money   If you fix the actual problem, it is permanent and the car should operate without a bunch of extra parts.

This may be met with some division, but I am yet to hear a good story involving an alloy radiator and electric fans set up on an old classic.
In my experience and from what I have read over the years, a good old copper/brass radiator with a mechanical fan is the way to go. This is what I have had on my car since I owned it (17 years). A year or so ago I had some overheating occur in the peak of summer, but that was quickly resolved with a proper radiator flush at a shop. For extra measure, I installed a 5-blade fan. The only other thing I might consider doing is fitting a fluid clutch type fan, but that is about it.
With the electric fans, these can actually block air flow...
 

I've had such a rusting problem in my 'parts chaser pick-up' I am running about a 1/2 gallon of white vinegar and tap water in it right now. I will flush it here "one-day" and see if with distilled water and anti-freeze it will be healed!
  Right now.............every time I drive it I start craving a salad with vinegarette dressing! Strange!!
6sally6

MS wrote:

Overheating problems start in the engine itself. You will eventually have to fix the actual problem. Bandaid fixes are temporary, at best, and cost money If you fix the actual problem, it is permanent and the car should operate without a bunch of extra parts.

I tend to agree, but if you are experiencing the problem when the transmission is working the hardest its not beyond the realm of possibilities that the trans fluid temperature is causing the coolant temperature to rise.  This would be most prevalent in a combination with a high stall speed converter on prolonged trips where the engine cruise RPM is below the converter stall speed.  The converter is slipping all the time, creating a ton of heat. 

Now if the coolant is getting hot just putzing around town, sitting at idle, etc. a trans cooler isn't going to do anything for that.