68 Barracuda 440 getting hot in traffic

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kmabry

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Any suggestions on how to keep my 440 cooler in traffic?
Runs 180 on the interstate but after sitting in stopped traffic for 10-15 minutes it starts to creep up to around 212-215 and then cools back down when moving.
 
Normal, deal with it. Those temps do not scare me. Keep moving!
 
Need lots more info. What size radiator is in the car? Is it a mechanical or electric fan? Is there a fan shroud? What temp is your thermostat? Do you know if you have a standard or high volume water pump? Are you running stock or aftermarket pulleys?

212-215 isn’t the end of the world if it stops climbing there, but it it increases to that and keeps climbing then you have an issue.
 
It has a 26 inch radiator and also has a a mechanical viscous fan.
There is a fan shroud that has been partially cut at the bottom for some unknown reason so it's not fully enclosed....I bought it that way.
Not sure about water pump and I think it has a 180 degree thermostat.
I drove it about 15 miles on the interstate to a car show today and it ran at 180 but had to wait in line at the show for about 15 minutes at idle when it happened.
It may have actually climbed close to 220.
 
It has a 26 inch radiator and also has a a mechanical viscous fan.
There is a fan shroud that has been partially cut at the bottom for some unknown reason so it's not fully enclosed....I bought it that way.
Not sure about water pump and I think it has a 180 degree thermostat.
I drove it about 15 miles on the interstate to a car show today and it ran at 180 but had to wait in line at the show for about 15 minutes at idle when it happened.
It may have actually climbed close to 220.

Run the Milodon High Flow 185 stat and a high flow pump from flowcooler.
 
It has a 26 inch radiator and also has a a mechanical viscous fan.
There is a fan shroud that has been partially cut at the bottom for some unknown reason so it's not fully enclosed....I bought it that way.
Not sure about water pump and I think it has a 180 degree thermostat.
I drove it about 15 miles on the interstate to a car show today and it ran at 180 but had to wait in line at the show for about 15 minutes at idle when it happened.
It may have actually climbed close to 220.

Do you know what pulleys are on the car?

Since it stays cool when moving more than likely the issue isn’t the radiator. Or the pump or thermostat for that matter. The fan shroud being cut isn’t ideal, you’re losing efficiency there. Since the car heats up when it’s depending on the fan for air flow I would make sure that the fan clutch is working as it’s intended. The other thing is if it has aftermarket pulleys you may be under driving the water pump, which also under drives the fan. Which reduces the amount of air the fan is moving.

Since it works fine the rest of the time I would start by looking at the fan, pulleys and fixing the shroud.
 
It does have stock pulleys on it and a 7 blade fan.
Is there any other fan that would be more effective
Thanks guys
 
In my opinion alone, it is was it is. Same on my 383. Little lower temps than you posted but used to be much higher until restore and a brand new 033 radiator. The Motor never suffered though, and had not been rebuilt since 1986.
 
You can spend hundreds of $ in a attempt to lower that temp a few degrees when you really have no issue. JMO.
 
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I will say this.......although my truck was not running hot, it was "more" temperature than I wanted it to run when I first got it. I've had it so long now, I honestly cannot remember the numbers, but I suspected the thermostat might be faulty, removed and tested it. I was right. It barely opened in a pot of boiling water. I replaced it with a Mr. Gasket high flow and the temperature dropped almost out of sight. It barely pulls the factory gauge off the "C" now, even on the hottest of summer days. That might be something to "try" if you want "a little more room".
 
I actually bought the car with the 26" radiator in it and no they didn't cut up the support to make the opening larger. That was another thing I was wandering if I should go with a different radiator because I'm not going to cut the support to make use of it.
 
My B-body BB engines never ran as hot as this A-body. Even with 2 core radiators. Since resto though this A body is tame with the correct radiator, pulleys and fixed 7 blade fan + shroud! Enhanced with the high flow stat and high flow pump.
 
It does have stock pulleys on it and a 7 blade fan.
Is there any other fan that would be more effective
Thanks guys

There are other fans out there but if you have a 7 blade fan already I would start somewhere else.

There are several different stock pulley arrangements out there depending on whether the car was an AC car or not, certain years, etc. It might actually be worth measuring the pulleys to make sure you don't have a mismatched set that's underdriving the fan and water pump. The other thing is there was a HV and standard pump from the factory, so it's possible you have a mismatch there, ie, an HV pump pulley set with a standard pump. I kinda doubt it since airflow seems to be the issue but it's possible.

Here's a list of cooling specs. If you already have a 18" 7 blade fan, then I would measure those crank and water pump pulleys to determine the ratio. If you're underdriving the fan it would hurt you at idle.

This is hard to read because of it's size, but if you go to MyMopar - Mopar Forums & Information - Service Manuals and download the 1970 Plymouth service manual and go to page 228 you can see a full size version. If you have a .95:1 ratio you should have an 8 blade water pump (HV), if you have an A/C car with a 1.4:1 pulley ratio you should have a 6 blade pump.
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Fixing the shroud will also help, a little bit of efficiency can make a big difference. And you should still check to make sure your fan clutch is working properly. If it isn't, your fan may be spinning slower than intended at idle.

In my opinion alone, it is was it is. Same on my 383. Little lower temps than you posted but used to be much higher until restore and a brand new 033 radiator. The Motor never suffered though, and had not been rebuilt since 1986.
You can spend hundreds of $ in a attempt to lower that temp a few degrees when you really have no issue. JMO.
I agree. You have no problem.

Guys, if the only reason his temp didn't climb above 215 is that he started moving again, he might have a problem. If it climbed to 215 in traffic and stopped that's fine, but that's not what he said.

Agree and if a 26” radiator did you cut up the support to make use of it? I only have the factory 3 core 22”.
I actually bought the car with the 26" radiator in it and no they didn't cut up the support to make the opening larger. That was another thing I was wandering if I should go with a different radiator because I'm not going to cut the support to make use of it.

There is no reason to cut the radiator support for the 26" radiator if it currently has an opening for a 22" radiator. For several reasons.

First, the car runs fine at speed which is when the opening in the radiator support would be restricting airflow. The car is heating up at idle, when the fan is moving all the air and the fan shroud means that air is in fact being pulled across the entire radiator core. So, the heating issue is when the entire core is having air pulled across it by the fan and the radiator support opening has no effect.

Second, even with a 26" radiator behind the opening for a 22" radiator, only a small portion of the core is covered by the radiator support. Like less than an inch per side, it's not a 22" opening. And the support isn't directly against the 26" radiator core. Which means even those outside tubes are exposed to plenty of airflow.

The advantage of the 26" radiator is additional surface area and volume. You still get both of those benefits even with the support for the 22" radiator. The 26" is still giving you better cooling than a 22".

I've run the 26" radiator in my Duster behind the stock radiator support for a 22" radiator for the entire time I've had it. It's never caused an issue for me. At speed the car has never had an issue with overheating, and at idle my fan shroud covers the entire radiator, pulling air across the whole core. There's no need to cut anything under those conditions.
 
I actually bought the car with the 26" radiator in it and no they didn't cut up the support to make the opening larger. That was another thing I was wandering if I should go with a different radiator because I'm not going to cut the support to make use of it.

Your choice alone! If you want to keep it then you have to decide. Finding a 3 core 22” can be tuff and may be costly but they are out there.
 
For many years I would get very nervous if my Mopar showed a temp much past 195, but when I got newer cars/vehicles I noticed that most run around 220 degrees, so on my 416 I really paid attention to the temp watching the electrical gauge I have (Speedhut) in the cluster and using a hand held IR thermometer. I discovered that gauge is not super accurate. I then tested out my 52 B3B (w/56 Desoto 330 Hemi) and discovered that the gauge in that as well as the EFI hand held were different than the handheld (mechanical gauge is quite a bi off). In other words, I discovered that unless the temps are getting to 220+ I am not overly too concerned. 200 - 215 wouldn't scare me too much.
 
For many years I would get very nervous if my Mopar showed a temp much past 195, but when I got newer cars/vehicles I noticed that most run around 220 degrees, so on my 416 I really paid attention to the temp watching the electrical gauge I have (Speedhut) in the cluster and using a hand held IR thermometer. I discovered that gauge is not super accurate. I then tested out my 52 B3B (w/56 Desoto 330 Hemi) and discovered that the gauge in that as well as the EFI hand held were different than the handheld (mechanical gauge is quite a bi off). In other words, I discovered that unless the temps are getting to 220+ I am not overly too concerned. 200 - 215 wouldn't scare me too much.

Heat will keep the engine clean of sludge to a point. I truly believe this is over hyped! My BB Mopar car ran the 1/8th best and consistently @ around 210 +/- 10 degrees.
 
Your choice alone! If you want to keep it then you have to decide. Finding a 3 core 22” can be tuff and may be costly but they are out there.

And may not solve the "problem", as the modern two row radiators are more efficient.
 
I will say on NOS it liked 190/185 better. But on pure motor. and no spray, happier at 200/210 degrees.
 
And may not solve the "problem", as the modern two row radiators are more efficient.

a totally untrue generalization. Some are, some aren’t. Depends entirely on what you’re comparing.

And he already has a 26” radiator, no ones even asked if it’s stock or aftermarket yet.

Glad you guys solved the problem he didn’t have already though.
 
a totally untrue generalization. Some are, some aren’t. Depends entirely on what you’re comparing.

And he already has a 26” radiator, no ones even asked if it’s stock or aftermarket yet.

Glad you guys solved the problem he didn’t have already though.

A 26” core does nothing when a 22” opening is all you have. Stay tuned. The OP has gotten what he asked for!
 
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