Help cooling 408 stroker

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fsoria1315

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I have a 69 Dart with a 408 stoker currently have a 22 inch Champion 4 row radiator and a 16 inch stage 2 Champion cooling Fan 2200 CFM. Car still runs hot and need some advice what I can do for more cooling. I only have little more then 2 and a half inches from radiator to pulley. What are my options?

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I don't think that's enough cfm. Choices are get a Mechanical fan, and shroud, or get higher output fans, and an electric fan shroud $$$.
 
I don't think that's enough cfm. Choices are get a Mechanical fan, and shroud, or get higher output fans, and an electric fan shroud $$$.
I put in a the electrical fan with a switch because it was heating up with the mechanical fan in stop and go traffic. I figured its not enough CFM but i have so little space dont know what to do.

I was thinking of getting a 2nd electrical fan as a pusher for the front side of the radiator and just offset both fans?
 
The pusher fan can cause an obstruction to air flow. 2 smaller fans with higher output would be better. Should give room for the water pump pulley. Does the temperature come down when driving?
If so, a Mechanical fan with a shroud will help. What temps are you seeing?
 
The pusher fan can cause an obstruction to air flow. 2 smaller fans with higher output would be better. Should give room for the water pump pulley. Does the temperature come down when driving?
If so, a Mechanical fan with a shroud will help. What temps are you seeing?

Any options that you might know of that has 2 smaller fans? When its hot out and my drive is climbing a hill it starts to run hot around 215-220 ish then starts to cool down once I level out runs around 200-210.
 
Any options that you might know of that has 2 smaller fans? When its hot out and my drive is climbing a hill it starts to run hot around 215-220 ish then starts to cool down once I level out runs around 200-210.
How about when sitting idling?
 
how thick is the radiator? i'm trying to figure out why you don't have more room. how thick is the 4 row?
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that's with March pulley's and a Hayden 2947 clutch
 
mine is a 3 row, tank is 2 3/4" and the core is 2 1/2"
 
My 4 row radiator is 3 inches thick. I kept the car running right now its about 98 degrees outside no sun but temp just kept slowly climbing even with the fan on. So might have to swap the radiators like you said for a 2 or 3 row radiator and get better dual fans
 
I have a 69 Dart with a 408 stoker currently have a 22 inch Champion 4 row radiator and a 16 inch stage 2 Champion cooling Fan 2200 CFM. Car still runs hot and need some advice what I can do for more cooling. I only have little more then 2 and a half inches from radiator to pulley. What are my options?

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A few things here..

-Personally, I don't feel 210-220 is too hot. I have a few muscle cars and 220 puts the needle straight up and down on the factory gauge, which would suggest that the factory felt that temp was ok.
-If you want to have better cooling, get rid of the 4 core rad. Yes, I know it sucks to shell out $500 for another rad. But, the key to cooling is surface area. Get a 2 core rad with 1.25" tubes. That way you have more fluid being exposed to cooling air flow. You will see a big difference.
-Are you running a 160 or 180 thermostat? If you have a 180, try switching to 160. This will allow water to start flowing at a lower temp and begin the cooling process sooner.
-How is your fuel to air mixture? Dropping more fuel into the cylinder which causes a hotter burn. You can drop 10 degrees just with a carb adjustment.
 
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I have a 3 core Champion radiator with their two 12" fan kits and my 408 runs in the 200-210 range pretty regularly. I have the early version where they used the crap Chinese eBay fans. Now their kits are offered with the 12" Spal fan upgrade which is a HUGE CFM difference. I'm going to try and change out my fans and see if I can't keep the temps under 200 degrees.
 
I would run a high flow water pump and make sure the pulley diameters were such that you overdrive the water pump slightly. 65'
 
Apperciate all the info gentlemen. I'm gonna go get a 2 row champion radiator on Thursday and then order the contour dual fans to install it.
 
Apperciate all the info gentlemen. I'm gonna go get a 2 row champion radiator on Thursday and then order the contour dual fans to install it.

Sounds like a man with a plan! Whatever you get, just confirm that the tubes are 1" at a minimum. 1 1/4" would be better.
 
A few things here..

-Personally, I don't feel 210-220 is too hot. I have a few muscle cars and 220 puts the needle straight up and down on the factory gauge, which would suggest that the factory felt that temp was ok.
-If you want to have better cooling, get rid of the 4 core rad. Yes, I know it sucks to shell out $500 for another rad. But, the key to cooling is surface area. Get a 2 core rad with 1.25" tubes. That way you have more fluid being exposed to cooling air flow. You will see a big difference.
-Are you running a 160 or 180 thermostat? If you have a 180, try switching to 160. This will allow water to start flowing at a lower temp and begin the cooling process sooner.
-How is your fuel to air mixture? Dropping more fuel into the cylinder which causes a hotter burn. You can drop 10 degrees just with a carb adjustment.

Temp has gone up to about 230 in a hot day and climbing a hill, cooled down to about 220 just cursing it. I'm picking up the 2 row champion radiator tomorrow, ordered the dual contour fan that ships on the 21st because its out of stock, once I install all that I'm gonna take it to the shop to get the carb adjusted.
 
I've done a 6 month research on what it takes to cool a performance Mopar . Several issues arise that is common to b.b. & s.b. . These are my results : the block and heater (if you are using one) must be clean . sounds basic but needs to be said . I would start with the least expensive upgrade and go up in cost from there . Next in line is a high flow thermostat (affordable) . going on from there is a high flow water pump . moving up in cost is an aluminum radiator (spendy) . Radiators come in all thicknesses but for this discussion we'll stick with 22". I have found that 2 rows of 1" or 1 1/4" tubes cool best . You get increased capacity and good air flow . The diameter of the pulleys must match . this is important for pump life . Hoses : use hoses designed for your car , not the universal convoluted ones . If you are not using a shroud , then get a 18" fan with a clutch if you have room . If you use a shroud , use a 16"15" fan . Belt : use a 5/16" wide belt , not a 3/8". the 3/8" belt doesn't set in the pulley deep enough and could fly off . Coolant : 50/50 green coolant with distilled water (not tap water), distilled water is cheap . Add water wetter and/or water pump lube as per directions .
One final thought : LA/BB/GenII Hemis were never designed to run at high temps (195*+) the cooler the better . Magnum/GenIII Hemis are designed to run at 195*+ and higher . Hope this helps , Tom
 
410 stroker.. $160 cheap Summit 2 core radiator... Big as I could fit ( not all that bigger than stock). Quality (meaning over 2500 CFM (thin as I could buy) 16in puller fan (of set to the driver side to fit).. with a thermal controller shut to 180°..
No thermostat... 1 to 1 Drive on a factory water pump..
Never seen over 205 and generally don't see anyting but 195 on the hottest days...
And if I can maintain 40 miles an hour or more the fan doesn't even come on...
For less than having someone tune your carburetor you could probably buy a wideband O2 sensor for about a hundred and sixty bucks and tune your own carburetor... And you'd also know if it needed it or not...
To reiterate if the car can't maintain temperature at 40 miles an hour consistent then it's has nothing to do with the fan..
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I also have to say before I added the big condenser radiator and a 12in electric Pusher fan the car would get down to 160- 170 on the freeway... Now even with that condenser and 12 inch electric Pusher fan in the way of the radiator when that 12in isn't running it still maintains 180 well moving down the highway. And definitely doesn't get / 195 when setting... Again it will have to be well over 95 degrees outside for it to get up to 200 or 205 (100° day) while at a standstill idling in traffic...
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sometimes i wish these cooling threads were divided regionally. i don't know what part of california fsoria1315 is in but kansas, oregon and so-cal have different kinds of summer. i want mine to live, parked in traffic for an hour, with it 115' out.
j par, i like the deflectors :thumbsup:
 
sometimes i wish these cooling threads were divided regionally. i don't know what part of california fsoria1315 is in but kansas, oregon and so-cal have different kinds of summer. i want mine to live, parked in traffic for an hour, with it 115' out.
j par, i like the deflectors :thumbsup:
We've had a string of 95 and upwards of a hundred degree days and those were the days that I tested... if you live somewhere where it's regularly 115 degrees we need to start another thread on why you would live in a place that's regularly 115 degrees...
 
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