Cooling situation

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9secRR said:
when i had my black R/T, the engine was an X block that was half filled, 13.5 compression, W2 heads. moroso electric motor to spin the water pump. i bought the flex a lite extreme electric fan that pumps out 3300 cfm. factory 1979 rad. i tried one day to see how hot it would get at idle.....i let it idle for 45 minutes and 180 is all it would do. i set the thermostat control nob to 175. fan cfm is very important.

with the blue car, i had a small tiny rad with a little electric fan, maybe 9''. i used the moroso electric motor to spin the edelbrock water pump. i leave the line at 150-155, at the top end it's 160-165, drive back to pits it's usually 170. half filled 340 block. i drive back on gas to get some heat in the engine to burn off the moisture from the methanol. i let the car get to 180-190 before i shut it off in the pits.

now i have a remote meizure water pump with aluminum rad and small 10'' electric fan. no idea what will happen yet but will soon find out.
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You’re running alky, right?
Completely different animal than gas. Sometimes with alky it takes planning to get enough temp in it.
 
I’d run it cooler from the get go if it were me. 140 at starting line is what I do. On way back the return road, usually shutting it off and coasting as much as you can helps keep the car from gaining so much temp after the pass. I run a 55gpm CVR electric water pump with a be cool radiator and 16” fan. Car really seems to like it. But I also run a big block so it’s probably easier to change electric inserts than your G3 hemi. But I’m not very familiar with G3s.

I’d say if it’s not too hard, maybe try a higher output electric pump.
 
B3422w5 said:
I was saying 180 street driving it. That is plenty fine.
I try to hit the water box at about 135-140 at the track. Usually by the ET shack getting my time slip it’s approaching the 180 mark
The key is staging the car at a consistent temp, running the electric water pump and fan allows me to dial the temp in to where it’s consistent, without the motor running.
Do you actually race? I know of virtually no race cars that don’t use basically the same procedure I mentioned above, at least if running gas.
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Yes. One of the worst mistakes I made was getting rid of the mechanical pump.

Again, just because it’s done by “everyone” doesn’t mean it’s the best option.
 
71Demon540 said:
I’d run it cooler from the get go if it were me. 140 at starting line is what I do. On way back the return road, usually shutting it off and coasting as much as you can helps keep the car from gaining so much temp after the pass. I run a 55gpm CVR electric water pump with a be cool radiator and 16” fan. Car really seems to like it. But I also run a big block so it’s probably easier to change electric inserts than your G3 hemi. But I’m not very familiar with G3s.

I’d say if it’s not too hard, maybe try a higher output electric pump.
Click to expand...
Since I have a motor plate with big block Chevy holes, it wouldn't take much to swap it out, just expensive. The CVR pump costs about 3x the Summit branded one. It's not a deal breaker, I might just do it at the end of the season. Do you run a thermostat or restrictor?
 
Here is an approximate of GPH flow of a Milodon high flow pump at 1:1. If you overdrive the pump you can do the math to see the GPH.

1000 20
2000 40-45
4000 70-80
6000 90-100 plus

Coolant flow is critical to cooling.

If the electric pump is actually producing 35 GPH (it’s likely not because of the way they measure flow) you are still down 55 GPH at 6k. And that’s at 1:1.

If you speed the pump up, then the electric pump is further behind.

I’ve checked the math and the power lost from turning the pump is canceled out by the power lost from not getting the coolant temperature in check.

But everyone does it so the math must be wrong.
 
"Here is an approximate of GPH flow of a Milodon high flow pump at 1:1. If you overdrive the pump you can do the math to see the GPH.

1000 20
2000 40-45
4000 70-80
6000 90-100 plus"

In my 8th mile drag racing situation, my RPM doesn't stay above 5000 for a second or 2. It's while at idle that I would like some improvement. Plus I have a motor plate that prevents me from running a mechanical pump.
 
There are 4 ways to increase cooling
1. Air flow
2. Coolant flow
3. Surface area
4. Capacity

Since on your car, the coolant flow, surface area, and capacity are hard to change, you might as well start with air flow. Your 12” fans are insufficient.
 
This is the fan I used. In my mind it’s the best fan out there. I had no problems at all.

IMG_1596.png
 
RockinRobin said:
Since I have a motor plate with big block Chevy holes, it wouldn't take much to swap it out, just expensive. The CVR pump costs about 3x the Summit branded one. It's not a deal breaker, I might just do it at the end of the season. Do you run a thermostat or restrictor?
Click to expand...
No thermostat or restrictor. Close friend runs 35GPH water pump. Car never gets hot.

I never did any math or anything like that when going with a rad and water pump. Just put biggest rad on I could fit with biggest fan I could fit and a good water pump.

Summits stuff now a days I believe is better quality than years prior. You may be shocked that it will do the job and be way cheaper.

But before I spent money, I’d try the free bee, start out running the car cooler, and shut it off and coast on the return road. Then re fire it up when you need to get some momentum
 

71Demon540 said:
No thermostat or restrictor. Close friend runs 35GPH water pump. Car never gets hot.

I never did any math or anything like that when going with a rad and water pump. Just put biggest rad on I could fit with biggest fan I could fit and a good water pump.

Summits stuff now a days I believe is better quality than years prior. You may be shocked that it will do the job and be way cheaper.

But before I spent money, I’d try the free bee, start out running the car cooler, and shut it off and coast on the return road. Then re fire it up when you need to get some momentum
Click to expand...
Actually launching at 160 degrees it finishes up the pass at 170 or so. I've tried running it full power at 145 before but it always lost a couple of numbers. Getting back to the trailer at 180 is not a big deal, I just wanted to be able to idle the car in the pits and not have it overheat. I'll try doing my regular launch but coast on the return road.
 
RockinRobin said:
"Here is an approximate of GPH flow of a Milodon high flow pump at 1:1. If you overdrive the pump you can do the math to see the GPH.

1000 20
2000 40-45
4000 70-80
6000 90-100 plus"

In my 8th mile drag racing situation, my RPM doesn't stay above 5000 for a second or 2. It's while at idle that I would like some improvement. Plus I have a motor plate that prevents me from running a mechanical pump.
Click to expand...


That is a bit of an issue. I know you can run a motor plate on a small block and a mechanical pump. I need to look at a BB plate.
 
RockinRobin said:
Are you pulling or pushing with this fan? Because of the electric water pump, I cannot run 1 big fan as a puller, not enough clearance. That's why I have 2 1500cfm 12" fans, so I can work around the water pump.
Click to expand...

If you are that tight on room you are kind of stuck. I know the Taurus fan will move air, but I think it would be too big to fit your chassis.

As TT5.9Mag said above, there are only four ways to increase cooling.

Can you get a 55 GPH pump? That would help.

If you lose power dropping coolant temperature it’s almost always a carb/booster issue.

I pretty much don’t do any carbs any more without a quality annular booster. Unless they are running a heated intake manifold. Then you get into issues with getting the fuel vaporized too soon.

That kills power too.

I have a carb coming that I’m putting together that’s getting annular boosters.

The 830 carbs I have for my tunnel ram has annular boosters.

All annular boosters are not equal.
 
RockinRobin said:
Are you pulling or pushing with this fan? Because of the electric water pump, I cannot run 1 big fan as a puller, not enough clearance. That's why I have 2 1500cfm 12" fans, so I can work around the water pump.
Click to expand...
pulling, fan was on engine side. it was tight fit. it's been so long since i had that car but i think it was only 1'' space to the water pump.
 
On both of my cars i run a mechanical pump, an 8 blade on the Duster and a flow cooler on the stocker, with a electric motor to drive them, i never have a problem with getting to hot, and i do not run an electric fan, but i start at 130-140, and don't idle my engines a lot, have a friend with electric pump, and has a hard time cooling it down even with a electric fan.
 
RockinRobin said:
Are you pulling or pushing with this fan? Because of the electric water pump, I cannot run 1 big fan as a puller, not enough clearance. That's why I have 2 1500cfm 12" fans, so I can work around the water pump.
Click to expand...
CFR makes 7" fans rated at 1500 cfm each, I have 4 on my champion rad and their amp draw is low only 3 amps, I have more heat than you have with twins but I stay below 190 after a run and sitting idle I get up to 210 and that's with a Meizer pump, 35gpm but that's at 12v my system is 14 so it makes a bit more, still might upgrade to their heavy duty where the base flow is 42 gpm just to run a little cooler.
7" HIGH PERFORMANCE ELECTRIC RADIATOR COOLING FAN - FLAT BLADE

20190523_164221.jpg
 
I've got a dual Derale fan and shroud assembly. The two fans are in the corners and gives you some room in the middle. It may clear your pump. But these draw a lot of amps. If your fan isn't drawing a lot it's garbage. Many sizes available but they are pricey.

Screenshot_20250425_074743_DuckDuckGo.jpg
 
Take one of those BIG squirrel cage fans from Harbor Freight and put it in from of the grill on high and start it. Is it no longer getting hot? Then that steers you towards insufficient fan. Still gets hot. I would then do what you stated. Measure the temp in and temp out of radiator. If it has sufficient temp change. You probably have sufficient cooling effect from the fins and tubes. You may have idle tune issue causing too much heat. You might try and flow test the pump. Remove the lower hose and put a garden hose in it so it supply’s uninterrupted water, then put a hose on the lower radiator outlet and then into a 5 gallon bucket. Time how long to fill the bucket. Same kinda thing as testing real fuel flow. Can’t hammer the water flow full blast or it will skew the result.
 
66Valiant528 said:
I've got a dual Derale fan and shroud assembly. The two fans are in the corners and gives you some room in the middle. It may clear your pump. But these draw a lot of amps. If your fan isn't drawing a lot it's garbage. Many sizes available but they are pricey.

View attachment 1716396922
Click to expand...
X2 on this fan set up. After fighting heat issues for too long than I care to remember, installed this. 2 speed controller never went into high on a street driven 450hp 340.
 
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