Coolant flow

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"Packing up", as you put it, is a rare problem usually only associated with flat plate style shrouds that come on the cheapest of cheap aftermarket electric fans. If a fan's shroud has flaps, that should be a dead giveaway is wasn't actually designed to flow air and that it was just slapped together and band-aided. There are a lot of aftermarket electric fans and shrouds that have no business on cars- their fan CFM ratings are too low, and their shrouds are simply a way to mount their cheap fans, not actually flow air.

I did read what you wrote, and you said "good mechanical fan" was necessary. It's not, a good electric fan and shroud work great. Maybe that's not what you meant, but that is in fact what you said.



You should care, because getting it wrong can mean cavitation in the water pump. The cars that had 1.3:1 and 1.4:1 pulley ratios had pumps with fewer blades. The reason is the RPM of the pump and cavitation, not the amount of water it's pumping. Running a high flow pump is good and the idea you can flow water too fast is silly, I agree. But, you still have to consider the RPM of the pump and how it's being driven. A 1:1 pulley ratio with a high flow water pump is one solution, but if your pulley ratio is 1.4:1 you need to account for that too. Some of the pumps are designed differently now, but the factory was looking at the pumps driven speed and adjusting the blades accordingly.


The majority of your points are right on and I agree, but you leave science behind on this point and just go with what you're personally familiar with.

The 180° temp thing is just left over from your drag racing background. Not every car/engine that gets discussed on this board is used the same way. If 180° was some magic number, the modern OEM cars would use it too. Yes, modern cars have to tune for a lot of other things too, but they all make higher hp/cube outputs than these cars ever did stock- they're more powerful and efficient. Sure, the engines discussed here usually aren't stock and don't have smog to worry about, but most of them also don't have nearly the control over their fuel delivery and ignition systems either. Literally no modern cars spec their water temps to be 180°, and a couple dozen degrees of coolant temperature aren't going to hammer your cylinder and exhaust temps so badly that you couldn't deal with meeting the smog and efficiency requirements. Modern OEM's could easily spec a 180° water temp if it made the most power or was the most efficient. They don't, and it's not because they don't know what they're doing.

If you were familiar with other kinds of racing, you'd know that pretty much only drag racing cars keep their engine temps under 180°. There are much crazier and exotic engine builds out there than make gobs of power for a lot longer than drag engines do and do it with much higher coolant temperatures. For a street car, it's not necessary or often even practical to keep the coolant temps between 160° and 180°.



Yeah, that's just BS. Modern cars pretty much ALL run electric fans, and some of them make more horsepower than dirt track cars too. Using a race car as an example is also usually a bad idea, since there are typically specific rules and regulations that require certain things and not others. And pretty much every automotive racing environment is highly specialized, and requires things that don't make sense on a street car. Why dirt track cars run mechanical fans instead of electric I don't know, but it's absolutely not because electric fans aren't capable of cooling those cars.

I have done the research on cavitation. And not just with automotive people. Cavitation is very rare unless the inlet side of the pump is restricted. Unless the hose is collapsing or some other issue is restricting flow to the pump the number of blades isn’t an issue. You’d have to show me real world examples of cavitation in automotive water pumps that were caused by too many blades.

180 degrees is the HOTTEST any of these engines should run and that’s not “left over” from my drag racing days. You are hung up on your number because you are stuck in your new car, hot coolant days. The “modern“ engine is nothing close to what we are discussing here. No one is using knock sensors and **** like that to pull timing on the stuff we are talking about.

Making power is about cylinder pressure. Cylinder pressure makes heat. Heat is power. Heat also promotes detonation. New (or “modern” like that means better…it doesn’t) engines deal with detonation by using knock sensors. They are also concerned with cold start emissions (I’m not), getting the cats lit (again, not a problem we are discussing here) and certain emissions levels (again, not relevant in THIS discussion) so trying to marry “modern” engine operation conditions to what most of what we discuss here is LUNACY.

But, here is the real clincher. Wait…I need to mention I haven’t done any work (as far as tuning and such) on any “modern” engine newer than about 2003 so keep that in mind…the real clincher is dropping the coolant temperature even on those engines increases power.

Now take off the EFI and all the related **** and drop a carb on one of those and run the coolant temperature up and see how fast detonation drops the power. It will start killing 20 HP so fast your hear will spin. And you have to add fuel and reduce timing (which makes more heat in the exhaust) which makes less power.

So get out of your head that coolant temperatures of 160-180 are a “drag racing” thing. Most drag cars have undersized, piss poor designed cooling systems that don’t control engine temperature like they should. That’s the big reason why drag racers (and corner turners) gain power when they switch to alcohol. They need the heat to vaporize the 2.2-2.5 times more alcohol than gasoline. Had they spent the money and time to unscrew their cooling system they would likely see little, if any gain from alcohol. And when that happens they see very little savings in fuel costs since it takes over twice the alcohol to make the same power as gasoline.

When I was tuning circle track engines (another group of people brainwashed that hot engines make more power) the FIRST thing I did after unscrewing their tune up was to make them buy a better radiator, a better pump and made them either sell or scrap their under drive pulleys. It was a fight for the first couple of people.

Once I was done, those guys finished 1 and 2 in points and neither one ran over 170 degrees. And all the long time smart circle track guys told them the engines would be junk when I did the freshen up at the end of the year. Of course, those morons were wrong.

I made them come to the shop on the weekends and they took their own junk apart. Then they watched me measure everything. We could have reused every part.

I have debunked the cool(er) engine temperature kills engines lie so many times its just stupid that it keeps coming up.

Again, these customers were running mostly on 3/8 dirt but they eventually went to 1/2 mile pavement. So the aero stuff doesn’t apply to them like it would to a car capable of more MPH, which is EXACTLY why cars at that level keep the coolant temperature as high as they do. I already talked about that somewhere else.

There is zero downside to running a cold(er) engine. I’d run mine cooler but at temperatures lower than 160 I can’t get defrost to keep the windshield clear.
 
False information [ post # 21 ] is still being given about t'stats, this time the Stewart Components Hi flow stats [ same as the Milodon & Mr.Gasket ].

The temp stamped on the stat is the opening temp, not the fully open temp as claimed in post #21. Fully open is another 20-30*. A 180 stat is not fully open until 200-210* & it an industry standard for t'stats. I have tested many of these over the years, using a digital thermometer.


Ok. Maybe where the toilets run backwards. I can run out and grab my 160 degree thermostat and drop it in water and watch it. At 160 its WFO. Just like every other Stewart Components thermostat I’ve tested.

There is no way my engine (or any of the engines I build and tune) could run at the rated temperature IF the ******* thing isn’t full open until 20 degrees above its rated opening. Explain that.

If the thermostat is rated at 180 and it STARTS opening at 180 (which means it ain’t open very far is it?) how do you have enough flow to maintain 180? You can’t.

Stop screwing up threads with bad information.
 
It might be surprising, but thermostats are controlled by a small pellet of wax trapped between a piston and cylinder. The opening point of the thermostat is the melting point of the wax. The thermostat design takes advantage of the change in volume of the wax going from a solid to a liquid. Wax expands by 17% upon melting which pushes the piston open. This happens over a 1-2°F range. Thus, there is no way that a thermostat will open over a 10-20°F range. I produced this type of wax using a synthetic process and know how this product is produced.
 
It wasn’t cheap $$ that’s for sure. Flat plate shroud with high CFM fan. It didn’t take long for me to discover it had to go. You may have known this from the beginning of time, at the time I bought it I had to find an 18 inch fan with shroud that would fit my situation for dragracing and street use. For that it was fine, although I had to run it more than I care to. It was no good for Highway use in my application. And that style is what I am referring to which is the exact same thing you are referring to.
Here's another example where the shroud design was the killer.
1941 Plymouth. Not much room. @MopaR&D figured it out first.
Shazam! Took the shroud off, fabricated new mounts and took it for a spin. At 70 mph, 91 degrees ambient, it stayed on 180! I guess my homemade shroud was too shallow and too restrictive after all. Looks like it will stay cool when idling with the A.C. on, as well. Thanks for everyone help And suggestions!

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The devil is in the details. (Kind of like @92b wrote, what setup is a best match can vary with application, and the constraints.)

Chrysler Thermostats

1966 Dodge Dart Coronet FSM
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^^^^^^^^
Opening has a plus/minus allowance of 5 F degrees.
Fully open is approximately 20 F degrees higher.

1970 Plymouth FSM
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^^^^^^^^^^^^^^^^^
Opening temperatures have a plus 4 minus 3 F degree allowance.
Fully open is about 20 degrees above the rating.

Flow
Full flow to the radiator was not expected until the temperature gets up to 200 degrees.*
This creates a variable flow situation. It means in very cold conditions, the coolant will exhange heat through the heater core.
On the other hand, in hot conditions (or when the engine is under load for extended periods of time) the coolant will exchange heat through the radiator.
*With the later cars using 190 and 195 degree thermostats full flow doesn't take place until 210 and 215 F.

However, that's not all folks.
When engine conditions created enough vapor, the coolant system would pressurize.
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You guys with those A-Bodies, and other alphabet cars, got it easy. Next time you’re out feeding your dog, take a look at that doghouse out back and imagine cramming a higher powered engine, radiator and all the accessories in there and making it run at a reasonable temp on the street.. And drag race the thing. And not boil you out of the box you’re riding in at less than a foot away from headers and all that convection taking place at stops. No slow pumps, no 195° thermostats, theoretical fantasies of making more power running at a higher temp. Pfft. As they say: “I know what I got”
Don’t tell me how it’s done. Yeah, as always, your results may vary. Happy cooling to you all, any which way you can. :lol:



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RB,
Peddler of bullshit & misleading information. Read Mattax's post #54. It explains in terms so simple that even you should be able to understand how a stat works: the rated temp is the OPENING temp, not the fully open temp.
It is obvious from your post #52 that you actually have NO IDEA how the cooling system works.
As for your 'findings' about a 160 stat opening in hot water, there are three possibilities:
- temp measuring device is faulty
- stat is faulty
- you need better glasses
 
I'm gonna go do somethin important. Like take a dump.

 
RB,
Peddler of bullshit & misleading information. Read Mattax's post #54. It explains in terms so simple that even you should be able to understand how a stat works: the rated temp is the OPENING temp, not the fully open temp.
It is obvious from your post #52 that you actually have NO IDEA how the cooling system works.
As for your 'findings' about a 160 stat opening in hot water, there are three possibilities:
- temp measuring device is faulty
- stat is faulty
- you need better glasses


Did you read post 53? Try that.
 
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You guys with those A-Bodies, and other alphabet cars, got it easy. Next time you’re out feeding your dog, take a look at that doghouse out back and imagine cramming a higher powered engine, radiator and all the accessories in there and making it run at a reasonable temp on the street.. And drag race the thing. And not boil you out of the box you’re riding in at less than a foot away from headers and all that convection taking place at stops. No slow pumps, no 195° thermostats, theoretical fantasies of making more power running at a higher temp. Pfft. As they say: “I know what I got”
Don’t tell me how it’s done. Yeah, as always, your results may vary. Happy cooling to you all, any which way you can. :lol:



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View attachment 1716086904
You need a frosty snow cone machine in front of that radiator.
I bet you could almost smoke meat in that engine house if everything isn't just right.
I give you a thumbs up on the fine job you've done with your van, very respectable.
 
You guys with those A-Bodies, and other alphabet cars, got it easy. Next time you’re out feeding your dog, take a look at that doghouse out back and imagine cramming a higher powered engine, radiator and all the accessories in there and making it run at a reasonable temp on the street.. And drag race the thing. And not boil you out of the box you’re riding in at less than a foot away from headers and all that convection taking place at stops. No slow pumps, no 195° thermostats, theoretical fantasies of making more power running at a higher temp. Pfft. As they say: “I know what I got”
Don’t tell me how it’s done. Yeah, as always, your results may vary. Happy cooling to you all, any which way you can. :lol:



View attachment 1716086891

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why you not using a fan shroud???
 
why you not using a fan shroud???
Haven’t gotten around to fabricating one (that is the only option) yet as I’ve been busy fabing other stuff. Temps don’t rise that much at stops or cackling around town at lower speeds to really give it consideration. Rise at longer stops at the most 10° if that. The small doghouse size and fan doing it’s thing may have something to do with that IDK.. I run anywhere between 160°-190° ish depending on ambient temps. I only drive it in about 40°- 85° temps as it takes a little easy driving initially to get temps up, the biggest issue in the cold is the lexan windshields fogging up as I have no heat, no wipers, no A/C, no thermostat, no bypass or heater hoses, only a disc equivalent to a gutted 160° thermostat by choice. Driving it in temps above 85° what’s the point. I run at the track with it too. I’m honestly in good shape now with my pulley combo, the hv water pump, aluminum radiator, and MP 5/blade w/Hayden viscous fan clutch etc.
 
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Haven’t gotten around to fabricating one (that is the only option) yet as I’ve been busy fabing other stuff. Temps don’t rise that much at stops or cackling around town at lower speeds to really give it consideration. Rise at longer stops at the most 10° if that. The small doghouse size and fan doing it’s thing may have something to do with that IDK.. I run anywhere between 160°-190° ish depending on ambient temps. I only drive it in about 50°- 85° temps (it takes a little easy driving initially to get temps up obviously but my biggest issue in the cold it the lexan windshields fogging up!) as I have no heat, no wipers, no A/C, no thermostat (no bypass or heater hoses, only a disc equivalent to a gutted 160° thermostat by choice) I run at the track with it too. I’m honestly in good shape now with my pulley combo, the hv water pump, aluminum radiator, and MP 5/blade w/Hayden viscous fan clutch etc.
What radiator do you have? You've obviously planned out the cooling system very well.
 
What radiator do you have? You've obviously planned out the cooling system very well.
It’s an FSR for a ground support Tug! One of those airport things that pull the luggage trailer around. Seriously. Had to find a size that fit, that was it. Two row 1” tubes, 18”x18” aluminum w/auto trans cooler In lower tank. Now they actually make one for the A100’s but at the time it was look for whatever I could make fit. It did take some trial and error with the fans: missteps and redo’s but now it’s there.
 
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It’s an FSR for a ground support Tug! One of those airport things that pull the luggage trailer around. Seriously. Had to find a size that fit, that was it. Two row 1” tubes, 18”x18” aluminum w/auto trans cooler In lower tank. Now they actually make one for the A100’s but at the time it was look for whatever I could make fit. It did take some trial and error with the fans: missteps and redo’s but now it’s there.
That's pretty cool. When I was lookin for an early Hemi, we went locally to look at one and that's what it was in. But it was a full blown aircraft tug. It was super cool, but the guy was way high on the price and it needed everything. Of course, all I wanted was the engine. But I eventually found one.
 
You guys with those A-Bodies, and other alphabet cars, got it easy. Next time you’re out feeding your dog, take a look at that doghouse out back and imagine cramming a higher powered engine, radiator and all the accessories in there and making it run at a reasonable temp on the street
I had a 63 Econoline. I added a SB Ford.

Same type of issues.

One thing I learned real fast is the pan between the bottom of the radiator and the front of the van MUST be in place to cool correctly.

It too had a tiny rad.
 
RB,
Yes I read post #53. What does it have to do, or say, about the opening temp of a stat relative to the number stamped on the stat??????

And if the poster is saying the stat opens over a 1-2*F range & that it will never open over a 10-20*F range, then he is as WRONG as you are....
 
RB,
Yes I read post #53. What does it have to do, or say, about the opening temp of a stat relative to the number stamped on the stat??????

And if the poster is saying the stat opens over a 1-2*F range & that it will never open over a 10-20*F range, then he is as WRONG as you are....

Are we talking about junk ****, cheap as dirt thermostats installed by Chrysler or an actual thermostat built for performance?


I‘m talking about the latter. As to the former, I don’t use junk like that.

Get your facts straight.
 
My facts ARE straight. Performance stats differ only from non-performance stats in the amount of coolant they can pass, NOT the temp rating.
 
Maybe one of you could put a pan of water on the stove with a thermometer and thermostat and show the other who is right.
 
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Mabey one of you could put a pan of water on the stove with a thermometer and thermostat and show the other who is right.
There is no question which one is right, if you have a t-stat rated at 180 that's not fully open until 190 then it's a 190 t-stat and is junk. Pretty simple but I am sure it will still be argued to death even though a guy that actually made them clarified how they work already.
 
Well I thought I would try to see things with my own eyes. I grabbed a new 180deg thermostat and a pan of water and heated things up. These are my observations on this ONE test on ONE thermostat. So in no way would I consider this conclusive.

1. heating water and holding the temp over time is challenging but necessary. Thermostats don't appear react quickly to changes in temperature.
2.suspend the thermostat sideways so you have easy access to measure the amount the valve is open. Drill bits will work for go nogo gauges.
3. The water will cook off as you test. Preheating make up water in the microwave helps prevent lowering the water temp if you have to add water.
4. Use two thermometers (Everyone is still going to claim they are wrong).
5. Have a clock, pencil and paper, camera, thermometers, go no go gauges and beverage of choice ready before you start the test.

My results were that the thermostat started to open about 180 deg and stay slightly open .010- .030" until heated to around 185 degrees when it opened to around 3/16". At around 190 deg. it was at a 1/4". 195deg. about .300" pretty close to fully open. Fully open seemed to be around 200 degrees.
This would be pretty close to what would be considersd a properly working thermostst according the info from the motor manual info provided by 12many and the Chrysler factory service manual info provided by Mattax. Also the info shared from Dicer.
 
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