Overheating 360 new engine

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When looking for a fan or fans would you total the cfm sum for both fans or per fan?
 
I don't mean to add insult to injury but...

Almost every post that starts with a "I have an overheating problem" , also states Aluminum radiator, electric fans, and fancy shroud. You almost never see one where there is a stock 2 or 3 core copper /brass radiator, factory or no shroud, and stock mechanical fan.

Just something to think about.
 
If I might suggest, get a factory clutch fan and proper shroud. I run one with stock water pump on my 550hp w2 408, no heating issues whatsoever. Although not sure if this can be done with serpentine system?????
This is another great option ^^^^^ if you're not dead set on electric.
 
I don't mean to add insult to injury but...

Almost every post that starts with a "I have an overheating problem" , also states Aluminum radiator, electric fans, and fancy shroud. You almost never see one where there is a stock 2 or 3 core copper /brass radiator, factory or no shroud, and stock mechanical fan.

Just something to think about.
VERY true and VERY good point.
 
If your fans don’t move at least 3,000 cfm they’re not enough, I don’t care what kind of radiator you have. There are really expensive fans out there that don’t move enough cfm. The Ford Contour fans I run will flow 3,500 cfm on the low speed setting and 5,000 cfm on high speed, that’s the ballpark you need to be in for electric fans on the street. Less than that won’t keep up.

You said you had march pulleys, whats the drive ratio on that water pump pulley? If you’re under driving the water pump too much it’s not gonna keep up. Most performance pulleys are under drive pulleys for more horsepower, they’re not made for cooling. You could have the “right” pulleys, but still have an under driven water pump. It’s all about application.

How many blades on your water pump? There are standard and high flow versions, they were designed for different pulley ratios.

The freeze plug blowing out it interesting. Might have a plugged passage in the block, although it could also just be a loose plug. I would suspect other issues first (like the fans not moving enough cfm). The cylinder temps will always be higher on the center two cylinders. If the right and left backs are different that could be a block machining deal, if it wasn’t square decked your compression ratio’s may actually vary side to side. Could also be a fuel issue, but if you’re TBI it shouldn’t be.
Wrong
 
Wow Late in the year for this overheating post!

Being an ASE Master Tech never helped me solve my overheating issues for to many years! In fact, they likely hindered it!!! We all think we know better!

Go back to the Basics is my opinion!

IE Your radiator is to small, Your Fan is inadequate, and who knows what else you may not have mentioned.

Going back to the Full Stock Config Parts after resto in 2014,including the shroud on my 69 Modified BB fish made the total difference! The Chrysler engineers knew what they were doing.

The car has not even burped in 8 years!
 
Does anyone know where I can purchase a 4000 cfm or greater fan?

If you have a 26” radiator you can use a Ford Contour set up like I do, lots more information here on my build thread on it

My "new" '74 Duster- or why I need a project like a hole in the head

When looking for a fan or fans would you total the cfm sum for both fans or per fan?

If you’re running dual fans you would add the cfm. So, if you had 2 single fans rated at 2,000 cfm individually that should be 4,000 cfm for both of them. That’s probably not exactly what you’d get, you don’t know how that fan is set up to produce that rating and just slapping it on your radiator might not get you the advertised specs.

Which is another reason to run fans that are designed to work together as part of a system, like the Contour fans are with their integrated shroud.

But that may only be part of your issue, there are a lot of other questions you need to answer. A cooling system is just that, a SYSTEM, it’s not just a really big radiator, or really high cfm fans, or a HD water pump. All the parts have to work together. You can install a really expensive radiator and fan and still come up short, you need all of it to work together.

I don't mean to add insult to injury but...

Almost every post that starts with a "I have an overheating problem" , also states Aluminum radiator, electric fans, and fancy shroud. You almost never see one where there is a stock 2 or 3 core copper /brass radiator, factory or no shroud, and stock mechanical fan.

Just something to think about.

First, that’s not true.

I know because I can remember multiple threads where members with overheat issues needed to add a shroud, or correct their pulley ratio, or match their water pump to their pulley ratio.

And you’re suggesting that aluminum radiators with electric fans are somehow less than the factory set up, which isn’t at all true. Not even a little. Electric fans are far more efficient than the factory mechanical set up.

The problem is that you just can’t buy a bunch of random parts and call it a cooling system. You need a radiator that can handle your horsepower output. You need fans with enough cfm. You need a way to control those electric fans so they run when they need to for the right amount of time. And it all has to work together. The most expensive parts doesn’t guarantee the best system.


Wow, now there’s a strong argument supported with facts and evidence. :rolleyes:

No, it’s not wrong. The Contour electric fans I run pull about 3,500 cfm on low and 5,000 cfm on high speed. Most of the time the low speed works fine, but on a couple of occasions when I’ve been stuck in traffic in 110°F weather I’ve had the high speed run as well. Granted most people don’t drive in that kind of weather with their classic, but I do. So yeah, under 3,000 cfm won’t work in any kind of real street driving anywhere it actually gets moderately warm. And if you drive when it’s HOT you need more than that.

Of course if you’ve got some show pony you trailer everywhere and barely drive you can probably get away with less, but on the street in real life driving situations it wouldn’t last.
 
Get rid of the toy fans.

Factory clutch fan with Hayden or similar severe duty clutch; matching shroud, blade tips close to shroud. If this gap is to large, the shroud becomes useless. Seal up shroud to rad gaps; & seal up rad to rad panel. Idea is that ALL the air should be pulled through the rad core, not through other gaps.
If you have a good quality alum rad, it dissipates heat better than copper/brass even though copper is a better heat conductor than alum. Reason for this is the large 1" tubes used in alum rads; they allow for a more efficient fin shape to be used & the fins are what dissipate the heat.
Another veeeeeeeeeeeery important point. i would like a $ for very car that I have improved the cooling on. The pump impeller should be closed off if possible. Any gaps means that the water is just splashed around, NOT captured to be pumped through the engine. Each blade section of the impeller should act like a scoop that has two sides....I often weld 'donuts', a metal plate to the impeller to make the scoop.
Use as much initial timing as possible. It makes the engine more efficient; when the engine doesn't have to work as hard, it runs cooler.
 
I don't mean to add insult to injury but...

Almost every post that starts with a "I have an overheating problem" , also states Aluminum radiator, electric fans, and fancy shroud. You almost never see one where there is a stock 2 or 3 core copper /brass radiator, factory or no shroud, and stock mechanical fan.

Just something to think about.
My 340, runs all year in Tampa, at 180, may creep a Lil at a long light w/ a stock set up. Except, I ditched the flex fan, and grabbed a clutch unit and fan. Still, never ran hot before that.
 
When looking for a fan or fans would you total the cfm sum for both fans or per fan?
Did that car run w/ Edelbrock heads and was kept at the shop on Gunn by Casey? Think it was a 340 then, with electric WP? Or is a different Purple Duster lurking about?
 
Another thing to remember when chasing a hot running engine.

There may not be any one 'thing' that reduces the running temp with a big drop...

It may be series of smaller changes that add up: better fan, tight fitting shroud, more efficient pump etc. If you make five improvements & each one knocks off 3*, there is 15* dropped.
 
I'm running the same setup, Holley Sniper, 3 core radiator, 180 thermostat, March pulley system, and my 360 is bored 30 over. Was reaching 220° now goes to about 205/6 when fan comes on high speed and will typically cool it down but it jumps back up in traffic. The Holley system is controlling the timing. I have it at 36° initially and to 46° on advance. Was running good with plenty of power but still getting a bit hot.
Went to take it out the other day and for some reason now it is running horribly at idle, rough/wants to die. Checked for fuel feeding both primaries(it has)..watching this post!!
 
If you have a 26” radiator you can use a Ford Contour set up like I do, lots more information here on my build thread on it

My "new" '74 Duster- or why I need a project like a hole in the head



If you’re running dual fans you would add the cfm. So, if you had 2 single fans rated at 2,000 cfm individually that should be 4,000 cfm for both of them. That’s probably not exactly what you’d get, you don’t know how that fan is set up to produce that rating and just slapping it on your radiator might not get you the advertised specs.

Which is another reason to run fans that are designed to work together as part of a system, like the Contour fans are with their integrated shroud.

But that may only be part of your issue, there are a lot of other questions you need to answer. A cooling system is just that, a SYSTEM, it’s not just a really big radiator, or really high cfm fans, or a HD water pump. All the parts have to work together. You can install a really expensive radiator and fan and still come up short, you need all of it to work together.



First, that’s not true.

I know because I can remember multiple threads where members with overheat issues needed to add a shroud, or correct their pulley ratio, or match their water pump to their pulley ratio.

And you’re suggesting that aluminum radiators with electric fans are somehow less than the factory set up, which isn’t at all true. Not even a little. Electric fans are far more efficient than the factory mechanical set up.

The problem is that you just can’t buy a bunch of random parts and call it a cooling system. You need a radiator that can handle your horsepower output. You need fans with enough cfm. You need a way to control those electric fans so they run when they need to for the right amount of time. And it all has to work together. The most expensive parts doesn’t guarantee the best system.



Wow, now there’s a strong argument supported with facts and evidence. :rolleyes:

No, it’s not wrong. The Contour electric fans I run pull about 3,500 cfm on low and 5,000 cfm on high speed. Most of the time the low speed works fine, but on a couple of occasions when I’ve been stuck in traffic in 110°F weather I’ve had the high speed run as well. Granted most people don’t drive in that kind of weather with their classic, but I do. So yeah, under 3,000 cfm won’t work in any kind of real street driving anywhere it actually gets moderately warm. And if you drive when it’s HOT you need more than that.

Of course if you’ve got some show pony you trailer everywhere and barely drive you can probably get away with less, but on the street in real life driving situations it wouldn’t last.
Wrong
 
Did that car run w/ Edelbrock heads and was kept at the shop on Gunn by Casey? Think it was a 340 then, with electric WP? Or is a different Purple Duster lurking about?
No it’s actually a 72 Demon . I live in lutz
 
Here is the clearance issues I have

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Sorry if you mentioned in earlier post, but unless something has changed since these photos, you need a shroud. Should have an air space about 1/2" back from the rad, forcing all airflow through fans. I suspect that alone will help greatly.


Here is what I’ve
Sorry if you mentioned in earlier post, but unless something has changed since these photos, you need a shroud. Should have an air space about 1/2" back from the rad, forcing all airflow through fans. I suspect that alone will help greatly.[/QUOTE

Here is what I've done this morning. I have advanced the timing as suggested in an above comment. This had no change on the overheating issue. Both fans are going the same direction and blowing towards the engine. The best I can tell the water pump pulley is 5 inches in diameter and crank pulley is 7.5 inches. I don't know how to configure the ratio. I still don't know the cfm of my fans. I suppose I may end up buying some fans that are shrouded so I know what cfm they are. I know some of you suggested going to a stock set up, but at this point I am to far into it. I am not willing to ditch my a/c p/s alt ect. for all stock parts. I see many vehicles running electric fans with no issue. I'm beginning to think as suggested above that the internal engine friction may be a real possibility. I plan to go ahead and get a shroud and have the timing controlled by my sniper set up. I am going to run a leak down test on all the cylinders. Mainly to make sure no air leaks are entering into the cooling system.
 
Here is what I’ve
Here is what I've done this morning. I have advanced the timing as suggested in an above comment. This had no change on the overheating issue. Both fans are going the same direction and blowing towards the engine. The best I can tell the water pump pulley is 5 inches in diameter and crank pulley is 7.5 inches. I don't know how to configure the ratio. I still don't know the cfm of my fans. I suppose I may end up buying some fans that are shrouded so I know what cfm they are. I know some of you suggested going to a stock set up, but at this point I am to far into it. I am not willing to ditch my a/c p/s alt ect. for all stock parts. I see many vehicles running electric fans with no issue. I'm beginning to think as suggested above that the internal engine friction may be a real possibility. I plan to go ahead and get a shroud and have the timing controlled by my sniper set up. I am going to run a leak down test on all the cylinders. Mainly to make sure no air leaks are entering into the cooling system.
 
OK cool. I'm right up the road from Ya.

So here is a fun fact. My radiator is a champion brand. They list a radiator with 2 fans and a shroud part # EC2374-2374FS10SP The fans are rated less than 900cfm each. This unit is rated for 375HP. Why such small fans??
 
if you look to control timing go that way:HyperSpark EFI Distributor, Chrysler Small Block 273/318/340/360
+Hyperspark box
contact the guys from Efisystempro for a quote.
Your fan system does not look adequate.....see also posts above.
Do you run antifreeze? You should!
Water is the cooling fluid, run 70 water 30 antifreeze mixture. Pure antifreeze is bad.
 
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