t stat

veno said:

what temp are you running now?

the T stat.. is a regulator for fast warm up... not necessarily a control item

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Man, there's nothing like a good thermostat debate LOL. OK explain how a thermostat isn't a control device. For instance, let's say your cooling system is capable of cooling your motor down below 160° at all times without a thermostat. I know it would have to be a pretty good cooling system to start with. Well if the thermostat is regulating the minimum temperature to 160° or 180° isn't it controlling the temperature?

I see it posted a lot that thermostat controls warm up time and a 160° thermostat will take longer to get the motor up to temperature. How does the water know to take longer to heat up if either a 180° or 160° is used? The coolant will take whatever time it needs to get to 160° regardless of what thermostat is in there right? Or does something magical happen and the coolant says to itself "oh look a 160° thermostat, I'm going to take longer to get to that temperature"... hardly.

Then you see a lot "a motor won't run cooler with a 160° thermostat" well that's a partial truth. No it won't run cooler if the cooling system isn't capable of cooling below that temperature or near it. But if it is it certainly will run cooler with a 160° thermostat compared to holding the temperature up at 180° with your typical 180° thermostat. It won't make the motor run cooler it will allow it to given the chance to do so. It certainly can't run any cooler than 180° with a 180° thermostat in it now can it?

The problem becomes people try to solve an overheating problem with a lower temperature thermostat. It's very hard to get through that the thermostat controls the minimum temperature but has nothing to do with the maximum temperatures. Again the cooling system has to be able to cool the motor below the thermostat's opening point or at least near it to see any benefit from a 160° thermostat. Sticking a 160° thermostat in a motor that's running over 200° won't do crap.

Now as far as the big 180° vs. 160° debate goes, use what you like. People have leapt off cliffs trying to prove one or the other is better. No one has ever proved a motor will be damaged with a 160° thermostat though many have tried to prove that non-existent point.

There's a lot of different ways to say the same things about thermostats, I myself have got caught up in semantics not understanding how one side or the other is explaining things.

Hey ALLT4,

not that I said it was not

is a regulator for fast warm up... not necessarily a control item

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and the key was

necessarily a control ITEM

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I think you covered all the bases in your question... Ya left me no wiggle room... you correct in that if the cooling system can bring the temp below a desired operation temp then the thermostat then becomes a regulator, However, if like most factory systems they are designed to operate in a temp range and the Tstat mainly is a warm up helper... after that it stays open and then is dependent on the cooling of the radiator and fans...

for example my sons 468 chevelle. with a 4 core copper and brass rad. the engine would operate at 210 regardless of tstat whether installed or not, the tstat in this case just aided in bringing the block up to temp quicker by holding the water in the block longer.. conversely, we install a 2core aluminum and have to run a tstat to bring the engine up to temp and maintain temp.

as for where the engine warms faster of slower based on the Tstat... that is a product of the engine its self.. IE: compression, thickness of the cylinder etc..

you know as well as I do that water warms to the temp of the tstat... speed of warming depends on the fire in the engine...


See ya

Veno

Mike Goble said:

The radiator doesn't need 'time' to do its job, it needs flow. The more water you flow through it, the better it works, same with the air side.

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Your wrong. Read my reply to your other post in the other thread about this. If this were the case why when you put a pan of water on the stove and even though the burner is really hot, why doesnt the water heat instantly? The time the water is spent in the radiator is calculated and thats what determines the size of the tubes, width of the radiator and its capacity. It needs to be the correct size for the engine your cooling. If your radiator isnt efficient enough, you can only do so much, speeding the coolant up (high flow) will make it worse. The water picks up heat faster than it can cool it.

So if your cooling something more flow of water will help like the engine, but if your trynig to cool the water in the radiator, in order to do so you'd need air traveling across the radiator sufficiently cooler than the temp you want to bring it down to. But you dont have that unless its winter time. I forget but every degree outside air will have a bigger effect on how it cools.
Your head (EGT) are around aprox 1200* your throwing water thats 190* at it and trying to cool that water and keep it at the same temp with air that is 75* The time the water remains in the heat exchanger (radiator) is very crucial. You want it in there as long as you can.....to a point where the engine isnt going to have the temp rise. So you want to keep cool water coming. High flow T-stats are good for drag racing....where you throw a lot of water at the enigne, and cool it good, but once it heats up you need time for the car to cool down. Drag racing isnt continuos so you have time in between to cool. So you dont need a super efficient radiator. Lots of drag cars have tiny radiators, enough to get the job done and thats it.

USN, MM, or United States Navy, Machinist Mate, grad from A school, Great Lakes, Il. 5th in class of 50

AKA stationary engineering and 650psi super heated steam 2400hp steam powered single turbine.

750 degree super heated steam ( dry steam aka Invisible steam)...

latent heats, heat travel, thermal transfer, direction of heat flow, length of exchanger, type of heat exchangers, conductive, passive, etc.. inlet manifold temp, outlet manifold temp...type of condensate, salinity of condensate... plus 10,000 other things I have forgotten since then...

Mike an I have had similar discussions... he knows very well all the jargon I just threw down....

the system as a whole has to be taken into account, not just one aspect...

as a whole, a complete cooling system should be built to incorporate a 30% larger direct transfer (conductive) heat exchanger than required with passive elements incorporated(fins), a pump capable of transferring coolant 30% faster than required and a regulator capable of maintaining the desired temp...

then it all boils down to where you want the engine to live in a temperate zone.

I sure wish I could remember all the crap pounded in my head back then in 1972 by the USN.. but to many child hood experiments have gone by.

Pwrtrip75 said:

Your wrong. Read my reply to your other post in the other thread about this. If this were the case why when you put a pan of water on the stove and even though the burner is really hot, why doesnt the water heat instantly? The time the water is spent in the radiator is calculated and thats what determines the size of the tubes, width of the radiator and its capacity. It needs to be the correct size for the engine your cooling. If your radiator isnt efficient enough, you can only do so much, speeding the coolant up (high flow) will make it worse. The water picks up heat faster than it can cool it.

So if your cooling something more flow of water will help like the engine, but if your trynig to cool the water in the radiator, in order to do so you'd need air traveling across the radiator sufficiently cooler than the temp you want to bring it down to. But you dont have that unless its winter time. I forget but every degree outside air will have a bigger effect on how it cools.
Your head (EGT) are around aprox 1200* your throwing water thats 190* at it and trying to cool that water and keep it at the same temp with air that is 75* The time the water remains in the heat exchanger (radiator) is very crucial. You want it in there as long as you can.....to a point where the engine isnt going to have the temp rise. So you want to keep cool water coming. High flow T-stats are good for drag racing....where you throw a lot of water at the enigne, and cool it good, but once it heats up you need time for the car to cool down. Drag racing isnt continuos so you have time in between to cool. So you dont need a super efficient radiator. Lots of drag cars have tiny radiators, enough to get the job done and thats it.

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It's you're wrong....

Where do I start? Let's start with the basic physics of cooling - the rate of heat exchange is directly proportional to the difference in temperature of the mediums. The hotter you make the radiator, the better it works, and the way to make it hot is to pump as much hot water through it as possible. The same scenario works on the air side, you want to pump as much cool air as possible through the radiator. At any heat load the radiator will have an average temperature that balances the heat dissipation with the heat absorption. If you lower the outlet temperature by slowing the flow, you must also raise the inlet temperature to maintain the average for the heat balance. This will show up as higher temperatures on your gauge.
The radiator is not a water cooler, it's a heat exchanger. Its job is to get rid of the excess heat of the engine, and the hotter it is the better it does its job.

Here are a couple of sites to begin your basic education on cooling systems:

Higher coolant flow will ALWAYS result in higher heat transfer. Coolant cannot absorb heat after it reaches it's pressure corrected vapor point. Furthermore, coolant absorbs heat at a progressively slower rate as it approaches this point.

http://www.stewartcomponents.com/Tech_Tips.htm

What would happen if we increase the coolant flow? Will it go through the radiator so fast that there won’t be time for cooling to take place? Not at all, from the expression, we can see that if the heat load is constant, increasing the coolant flow rate will reduce the coolant temperature drop through the radiator, resulting in a higher bottom tank temperature. If the bottom tank temperature is increased, the top tank temperature must go down to maintain approximately the same average core temperature.

http://www.arrowheadradiator.com/14...apability_in_high-performance_automobiles.htm

It's just basic physics.

veno said:

USN, MM, or United States Navy, Machinist Mate, grad from A school, Great Lakes, Il. 5th in class of 50

AKA stationary engineering and 650psi super heated steam 2400hp steam powered single turbine.

750 degree super heated steam ( dry steam aka Invisible steam)...

latent heats, heat travel, thermal transfer, direction of heat flow, length of exchanger, type of heat exchangers, conductive, passive, etc.. inlet manifold temp, outlet manifold temp...type of condensate, salinity of condensate... plus 10,000 other things I have forgotten since then...

Mike an I have had similar discussions... he knows very well all the jargon I just threw down....

the system as a whole has to be taken into account, not just one aspect...

as a whole, a complete cooling system should be built to incorporate a 30% larger direct transfer (conductive) heat exchanger than required with passive elements incorporated(fins), a pump capable of transferring coolant 30% faster than required and a regulator capable of maintaining the desired temp...

then it all boils down to where you want the engine to live in a temperate zone.

I sure wish I could remember all the crap pounded in my head back then in 1972 by the USN.. but to many child hood experiments have gone by.

Click to expand...

What difference does it make what education or job title you have/had?
I have absolutely no formal training in a lot of feilds yet have "experienced proffesionals" seeking my help and advise. Who taught the first teacher??

This is my point (in red). Of corse you can blast the water through the radiator at an insane speed, IF the radiator was designed to cool the engine and maintain it at the temp you want it would work. The factory system is engineered to work how it is designed. The speed/flow/capacity is all taken into consideration. You have 2 items exchanging heat....the engine, and the radiator. To maintain the proper temp they have to work together. Sure the radiator is still working at 250*. But how effectively is it bringing your op temp to 195? ...not very.

Mike... my point is "Higher coolant flow will ALWAYS result in higher heat transfer"... Yes.... you'll transfer the heat from the engine faster. But do you think you can transfer the heat from the radiator just as fast? Many many people and experience myself tell me no. Im not saying its impossible, but you would have to make dramatic changes to remove heat from the radiator to maintain the ideal temp. Either a larger one, more air flow (fans). So creating higher flow alone without modifying the whole system will just give you problems.
Thanks for the spell check.

You guys need to think of the whole scenario before fireing come backs. The laws of physics are just that... now put them into reality and real life context and you have to allow for fluctuation and other variables. Its called COMMON SENSE. You can be a master at physics, but if you cant tie your shoes or walk and chew gum at the same time.... how far will ya get?

Hey Pwrtrip,

the education was to Clarify a point of reference... (I was not collocating egregious indignations or falsehoods) I have lived, operated, and repaired on a very large scale: air to water, water to water, air to oil, water to oil, steam to water, heat exchangers, some with sea level pressures some with 29.9 inches vacuum. which operate a little different than atmospheric pressures exchangers...

I have a q: for you..

1 which way does heat flow? or in what direction?

2 can you have water at the same temp yet be in two different states? ie 32 degrees, and 212 degrees..

If water changes state from a solid @ 32f and again @ 212f and again at around 350f to superheated steam..

3
Can 3 states exist at change state temps? can 6 states exist all within the change states??. can it be water @ 32f if it is ice? can it be water @ 212f if it is steam? can it be saturated steam @ 350 if it is super heated steam?

assume sea level..


ya have to know how heat moves, and the direction it moves, and the conductive aspects of the things your trying to cool or heat... cause thats what your doing.. your cooling one exchanger and heating another... and the out put and input is dependent of the properties of the componets as a whole..

TY70SS said:

In my 406 I don't run one.It runs cooler with out one.I don't know why but it does.So far this year I went 6 back to back runs spraying 150 shot it 90 degree heat and the car never got over 190.So I say try without one and with a thermastat and see what your motor likes best.

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Pwrtrip75 said:

What would happen if you drove it 100 miles? Every application is different. Rich/lean conditions can also make or break you.

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I believe that's why he used the wording he did. :yes:

Talk about who's getting fired up and shooting out comebacks without truly reading and comprehending what was posted in the first place.:devil:

Personally, I like to run MORE radiator than is what's required to keep my engine cool. The factories these days barely use enough radiator to cool the engines so once the t-stat opens it stays open. The problem with that thinking is if there is ANY problem (few clogged tubes, restricted airflow because of build up in front of the radiator [bugs, dirt, etc.], low fluid level, etc.) and the car will start to run hot. I like running my builds right on the edge (hence my sig) so I don't want that worry.

Finally, something else to consider. If you slow the water flow down in the radiator you're also slowing the water flow through the engine. The major problem with that is allowing air/steam pockets to develop because the water flow isn't sufficient to "Flush" the system out or keep enough cooler water flowing over the extreme hot spots like the tops of the bores and between the center 2 exhaust ports. Just a thought..

And yes, I work on a FEW all out drag apps that are running NO radiator and one that's running completely DRY.. Full out drag cars are different animals than street cars when it comes to cooling needs. Now on the other hand, an SCCA car would make a better comparison..:yes: