opinions needed on this idea

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trudysduster

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In my Duster I am running a 440 and I have a factory radiator, 26" that has been in there for a long time now. Last year before I took this to Cruisin the Coast I pulled it and had it checked at a local radiator shop and he said it was flowing fine. Didn't see any problems with it. It has been in the car for about 17 years now since the 440 was installed. It cools ok but sometimes in the summer when it gets hot and I have gotten in stop and go traffic or spend a long time at a drive thru the idiot gauge runs up about 1/2 way. some say that is normal. Why don't I put a set of gauges in the car that shows numerals. Because I have restored this car and I show it and I think it doesn't look good. But my idea is to get a new Champion radiator, 26 " and keep the factory fan and then mount a set of dual Spal fans on the front of the radiator. Is that overkill or what. The main reason I am thinking about this is that this year when we take the cars to Cruisin the Coast, I want to run them in the Long Beach parade. Right now I don't believe it would make it without getting hot. I cant imagine that the radiator being 17 years old would be cooling at its maximum capacity. I even thought about just getting the radiator and running it over the summer and see how it does without the Spal fans on the front. But I didn't know if a lot of people ran factory fan blades with electric fans pushing from the front.
 
If your BB only goes to half way your doing pretty good. My 94 van runs at 3/4 and my SB valiant runs just over 1/2 with a clutch fan.
 
Temporarily tie in another gauge to confirm "the idiot gauge" read out. You may be just F&D.
 
Temporarily tie in another gauge to confirm "the idiot gauge" read out. You may be just F&D.

Yeah, I guess it would be better to run a temporary gauge and see where I am really at. Then if it is running too high put the fans on this one. I guess it would be better to run 2 -12" than 1 16" fan. I just put a new Champion radiator with a Spal 16 " fan on this rat rod I am building. I just thought that new aluminum radiator would look real good under the hood. I think I was looking for a reason to get one. lol
 
well ... there's always the "take out the thermostat" and "keep the heater and blower motor on" in traffic route... in the Marines, we used to call that kind of mechanical work "combat repairs"...
 
If you take out the thermostat the water will flow to fast and not have time to cool in the rad, get a actual temp gauge and hook it up so you know the real temp and stop guessing!
 
I guess my biggest thing is that, lately, when I'm buying oem style parts, twenty year old oem works better than the new (usually Chinese) stuff.
 
If you take out the thermostat the water will flow to fast and not have time to cool in the rad, get a actual temp gauge and hook it up so you know the real temp and stop guessing!


brian...

i'm curious about your response.. years ago when i was still living in "the hills of w.va." taking the thermostat out of a car that ran hot was always the first "remedial" action - and always was good for at least a 10 degree temp drop. back then, i believe there were two thermostats - a 160 degree and a 180 degree. we used to call them "hot" or "cold" ones. it was common when removing the thermostat from an overheating car to find the thermostat to be rusted and stuck in place not allowing the baffle plate to open under temperature. by your theory, running with no thermostat would result in the car also overheating. but i never found that to ocurr once i removed the old rusted thermostat. in fact, a lot of cars during the summer would not have thermostats and they would only be reinstalled "when it got cold" so the heater would work!! do you have more information on your view?

are there other FABO "experts" out there that want to join this debate? please no angry responses... !!
 
brian...

i'm curious about your response.. years ago when i was still living in "the hills of w.va." taking the thermostat out of a car that ran hot was always the first "remedial" action - and always was good for at least a 10 degree temp drop. back then, i believe there were two thermostats - a 160 degree and a 180 degree. we used to call them "hot" or "cold" ones. it was common when removing the thermostat from an overheating car to find the thermostat to be rusted and stuck in place not allowing the baffle plate to open under temperature. by your theory, running with no thermostat would result in the car also overheating. but i never found that to ocurr once i removed the old rusted thermostat. in fact, a lot of cars during the summer would not have thermostats and they would only be reinstalled "when it got cold" so the heater would work!! do you have more information on your view?

are there other FABO "experts" out there that want to join this debate? please no angry responses... !!

well, just so we are on the same page, I don't believe I said anything about the car overheating. I said it ran up about 1/2 way of the factory gauge. Which I have no idea at what temp that is. I am only going by the fact that it doesn't do that with normal driving and the normal temps. With normal driving and the gauge stays on the low side of the gauge and having a 180* thermostat in there I am assuming that the temp is rising around the 200* mark or a little higher. Some say that is normal and ok, but I think that is a little high for me. By running a fan on the other side, I am sure it will bring it down some better to my satisfaction. I was just wondering if that is too much. But I am going to get a numerical gauge and put on it to check it.
 
For a few bucks you can get a infrared temp gun from Summit and you can check the temp without violating anything.I think mine was $35.00. Use mine all the time in checking individual cylinder temps off of the header on my sprint car

IMG_0567.JPG
 
i'm still curious if any other "technical" FABO readers have an opinion on the "no thermostat makes the car run cooler" debate.

however, i can say with some confidence that "old" V8's - like your 440 - DO NOT like "heat." in fact, all V8's from about 1958 to 1978 do not like heat. in the 1950's and 1960's, the majority of cars ran 100% "water" in their cooling systems. since water boils at 212 degrees, normal running temperatures were based on the 160 and 180 degree thermostats. it was not uncommon "back then" for cars to overheat on hot days or in traffic because engine temps would reach the 212 boiling point even with properly functioning thermostats. in the 1970's, "cooling antifreeze" came on the market and helped the overheating problems. by then, almost all cars were running some kind of "synthetic" liquid in the cooling systems, NOT just water. when air pollution and emissions laws got going, engine operating temps went up as a hotter engine burns off more emissions. today with synthentic oil and cooling liquids engines are designed to run hotter than in the past. i believe the average engine today runs around 200 degrees.

your 440 is going to be happy the "cooler" it can run. years ago in the late 60's and 70's when i was in high school and drag racing mopars, my cars were always faster in the fall and winter because of the air temp. in fact, there was a product back then called a "cool can" which i installed on a Roadrunner i had for a while. it was an alluminum can about the size of a regular coffee can that had a coiled copper tubing in it that you hooked your fuel line to. when you were going to race someone, you filled the can up with ice which cooled the fuel prior to entering the carb. a "cool can" was good for a couple of horsepower.

so i would do whatever you can to keep your big block cool - a larger radiator, electric fans, running your heater all the time ... you get the picture...
 
Well, JimHarvard, I guess my engineering training doesn't permit me to agree with you. While it is correct to say engines run better, when cool, there is an optimum point beyond which being too cold hurts performance. Todays modern cooling systems use the thermostat to throttle the flow of the coolant to extract heat from the engine. Its been proven many times that flow without a thermostat prevents the flow of coolant from removing heat from the engine because the coolant moves too fast to absorb the heat. So I respectfully disagree with JimHarvard regarding cooling. Excessive heat will rob an engine of performance as will a cold engine. I've found over the years with todays engines, pressure radiators and coolants operating temperatures from 195F to 220F work just fine. Just my opinion.
 
Well, JimHarvard, I guess my engineering training doesn't permit me to agree with you. While it is correct to say engines run better, when cool, there is an optimum point beyond which being too cold hurts performance. Todays modern cooling systems use the thermostat to throttle the flow of the coolant to extract heat from the engine. Its been proven many times that flow without a thermostat prevents the flow of coolant from removing heat from the engine because the coolant moves too fast to absorb the heat. So I respectfully disagree with JimHarvard regarding cooling. Excessive heat will rob an engine of performance as will a cold engine. I've found over the years with todays engines, pressure radiators and coolants operating temperatures from 195F to 220F work just fine. Just my opinion.

Can you elaborate on the " todays engines " run from 195 to 220 just fine. You talking about cars of the 2000 up or are we talking about the cars from the 70's.There is a big difference in the engines.
 
Can you elaborate on the " todays engines " run from 195 to 220 just fine. You talking about cars of the 2000 up or are we talking about the cars from the 70's.There is a big difference in the engines.
All engine regardless of age need heat to operate efficiently. when the engine heats up, pistons expand rings seat, etc. Think about it, why else would high performance engines like funny cars or pro stockers put heat into the engine before each run. Cars of the 60s, 70s, and up require engine heat just as todays cars do. I can't remember a car I built that didn't run around 185F. Granted 220F in a 1967 Chevy might be reason for alarm, but then cars weren't running 16 pound radiator caps either. As a kid 60 years ago we ran flatheads without thermostats and without radiator pressure caps. a lot has changed since then. My Gen 3 Hemi will be in the 195-220F range with a 16 pound cap and will will do just fine.

My point is to say "run the engine as cold as you can" isn't helping the engine. just my opinion
 
well... finding the answers to questions has always been an interesting challenge to me. most of the research i did on old mopar and chevy engines, small blocks and big blocks found that those engines liked to operate between 160 and 200 degrees - but no hotter. with that said, here is a rather LONG article that i found discussing a lot of ideas about engine cooling. this article also notes that it is NOT a good idea to run with any thermostat at all but that practice was "popular in the South" - i guess that explains why it was so popular in w.va. this article was written by an engine builder. it's an old article and i do not know if these guys are still in business - www.diamondbackengines.com

Overheating-boring white paper
First off, you DO want a certain amount of heat in your engine-technically, from a strictly book position, you want to run it as hot as possible without damage. Obviously, there are limits and in particular, we generally figure the damage point to be 252F. That said, a good operating range is between 175-230 degrees F. But you say, mine runs better when it's dead cold....well maybe it does, however that would point to the engine being tuned improperly- typically the carb being too lean.

NEVER EVER hammer on an engine until you have at least 150 degree temp ... WHY? well because the parts inside to include bearing clearances, piston to cylinder clearance and head gasket crush change as they warm up- if you go blasting thru the neighborhood at 75 degrees engine temp, you invite piston skirt problems, oil circulation issues and if there's enough compression, blown head gaskets. I like to see no more than 220-230F running temp. Preferably a little lower, because you have no real safety zone otherwise. Don't expect your roller cam 14/71 blown big block to run at 165 degrees- the more power you make, the more heat there is to dissipate.

Now on to some specific hints:
If it always ran fine and now all the sudden it's too hot then before doing anything else, check the most likely culprits:

RADIATOR CAP SHOT-take it off and observe the rubber gasket. If it looks like it's not touching anything when it's installed, or the rubber ring doesn't exist, or it's all cracked and nasty-replace it. Many times this is all it takes- if there is no pressure developing, the coolant will boil earlier than normal, turn to steam and not cool effectively.

LOOSE HOSE CONNECTIONS- look for signs of coolant dribbling down the hoses or stains- again loss of pressure.

LOOSE Fan belt - Typically will squeal, but not always- if it slips, the water pump is not spinning properly
OTHER LEAKS=self-explanatory

New motor just built: First off narrow down the problem- does it run hot (1) ONLY AT IDLE? (2) ONLY AT HIGHWAY SPEED? (3) ALL THE TIME?

If (1) ONLY AT IDLE, you more than likely have a fan problem, as that is basically the only thing moving the air across the radiator at that point. Logic here is once the car is moving the air flowing thru the grill is keeping you cool. If it's a clutch fan, spin it by hand (WITH THE ENGINE OFF) and note how much it turns before it stops- more than a turn or so and it's time to buy a new one.

not that? - do you have a fan shroud and is the fan properly located in it?
The shroud is designed to force the air to follow a path thru the radiator-cool air from the front across the radiator-without one, you are likely just stirring up the hot air under hood and wasting a large part of the fans ability to cool. The fan should be located +/- about 1" from centered in the rear opening-too far back and you lose the effect, too far forward and you create negative vortexes and actually "stall" the airflow. While on the fan subject, a high quality clutch fan is usually your best bet as it somewhat freewheels at high speed saving power and self-destruction.

Another one of my favorites is the notion of taking off the mechanical fan in favor of an electric one. While there are cases (no space engine swaps) where this may be the only option, there is usually no good reason for this on the street in my opinion. Why would I say that? Well, you are giving yourself another reason to be dead on the side of the road- if the engine is running, a mechanical fan is turning- an electric one may give up at any time, leaving you with no low speed cooling. But, you say, I am saving HP- not necessarily. Nothing is for free- in the case of a drag car with no alternator or a cut off, yea, but on a street car, the increased load is directly on the alternator which in turn takes more HP to spin, thereby negating most or all of your perceived gain. IF you must use that method, get a good high cfm fan. the little $69.95 jobs don't move enough air to cool a lawnmower.

If it's not the fan, did you install a fancy big water pump pulley to save HP? If so, take it off and try your stock one-many times the reduced speed caused by these pulleys not only slows the fan down but also slows the water pump speed so that normal water flow becomes something akin to a lazy snail moving thru the engine causing steam pockets etc...Same thing goes for the big alternator pulley that causes your charge gage to go negative at idle.

Improper base timing- if you are not getting enough total timing, the engine will tend to run hot as much of the power is going right out the exhaust- the burn cycle initiates and therefor ends late- extreme cases can find the fuel mix still burning strong going out the exhaust, but at the very least you need more throttle for any given speed, causing the engine to work harder.
If it's not any of these, see section (3)

IF it's (2) ONLY AT SPEED, it sometimes gets more complicated...Easy things first:
Collapsing lower radiator hose- there should be a spring inside the lower hose to keep the water pump from squeezing it flat at speed- if your lower hose is the slightest bit mushy and there's no spring, this is a good starting point-you can sometimes make a coil tightly around the outside of the hose with a coat hanger (or the inside if you are inclined) to test this- if it's better or fixes it, buy a hose with the spring or buy the proper one and one of the flexible hoses to steal the spring out of.

No Thermostat- very common in the South and many times causes the coolant to flow too quickly at speed, not allowing time enough to cool in the radiator- you don't have to buy one of the fancy 15 dollar restriction devices - simply grab one of your junk thermostats or stand in front of the parts store and beg for somebodies old one- snip the u shaped piece off and remove the guts-now install the ring in place of the thermostat. While on the subject, thermostats are generally a good idea especially in climates where there are a lot of days under 80F- they bring the engine to temp quicker.

Improper max timing- if you are not getting enough total timing, the engine will tend to run hot as much of the power is going right out the exhaust- the burn cycle initiates and therefor ends late- extreme cases can find the fuel mix still burning strong going out the exhaust, but at the very least you need more throttle for any given speed, causing the engine to work harder. If all else is fine and you have your vacuum advance disconnected, try re-hooking it and see if your problem disappears. If you built a 18:1 iron head motor go buy some decent fuel and set your timing where it belongs. If you need much less than 30-32 degrees on a Mopar to keep it from detonating, you need better fuel. Over advancing will cause issues also, but will generally result in audible knocking.

Radiator too small- this will generally fall in number (3), but a radiator right on the edge may cause high speed only issues.

On Automatic cars, too much stall speed- If your stall speed is much above your cruise RPM, the transmission will overheat and cause the radiator to do more work - this will also burn up your trans.

Too small/smashed/plugged up exhaust- causes the engine to work much harder to maintain speed. Usually also results in poor performance.

Dragging brakes-same effect as above.

Mixture too lean- check your plugs after a medium range cruise (try not to idle much at the end)- if they are white or burnt looking, jet up 2-4 sizes and see what happens.

IF it's (3) ALL THE TIME- is your thermostat opening? see if the upper and lower hoses are roughly the same temp - or leave the cap off when cold (DON"T YANK IT OFF WHEN HOT) and watch to see if it circulates when it warms up. IF not, replace the thermostat (don't leave it out or throw it away-see number 2 for explanation)

Does the front of your radiator resemble a graveyard for various flying objects? If it's full of bugs and mud, it won't cool-spray out the fins and see what happens.
Did you overbore the engine more than .040? Many time over boring .060 or bigger creates cooling problems due to inadequate heat transfer- those 3 extra cubes are going cost you big bucks for a massive cooling system.

Overall Lean condition-see 1 and 2 for explanation
Weak spark- if you have a weak spark, the engine will burn erratically and can overheat as a result.

Clogged up radiator- if it came stock in your 1956 Belvedere it probably needs rodded out or re-cored
Many other things can cause constant overheating such as high internal friction (inadequate clearances etc.) but that will usually result in a poor running engine.
 
For a few bucks you can get a infrared temp gun from Summit and you can check the temp without violating anything.I think mine was $35.00. Use mine all the time in checking individual cylinder temps off of the header on my sprint car

View attachment 1715040530

I checked Summit for one of these and came up way more than the $35 you said. Do you have some kind of a part # from them.
 
Something I do to every thermostat is to drill a 1/8" hole in the flat part, so there is a little antifreeze flowing thru at all times.
This seems to work fine in my old flat-head engines, old mopars, jeeps and modern cars.
 
The statement "water flows too fast thru the radiator to have time to cool" is commonly spread among hot-rodders. It has no basis in science (my M.S. thesis was in heat transfer). An engineer at Stewart ran across this and was so amused that he ran down the source (Stewart Components). The idea came from vintage cars (1920-20's) where a weak radiator cap spring would burp fluid due to increased flow pressure of a tuner water pump. A restrictor fixed that, but the guys mis-understood why.

As mentioned, you can buy an IR gun at Harbor Freight for $25 on sale. Mine works amazingly well against a mercury thermometer when checking T-stats in a pot of hot water. Running w/o T-stat wouldn't prevent over-heating unless it gives too much restriction in the "full-open" position (unlikely). It will over-cool the engine in the winter. Don't buy a "fail-safe" T-stat since they permanently lock open if you ever over-heat.
 
The statement "water flows too fast thru the radiator to have time to cool" is commonly spread among hot-rodders. It has no basis in science (my M.S. thesis was in heat transfer). An engineer at Stewart ran across this and was so amused that he ran down the source (Stewart Components). The idea came from vintage cars (1920-20's) where a weak radiator cap spring would burp fluid due to increased flow pressure of a tuner water pump. A restrictor fixed that, but the guys mis-understood why.

As mentioned, you can buy an IR gun at Harbor Freight for $25 on sale. Mine works amazingly well against a mercury thermometer when checking T-stats in a pot of hot water. Running w/o T-stat wouldn't prevent over-heating unless it gives too much restriction in the "full-open" position (unlikely). It will over-cool the engine in the winter. Don't buy a "fail-safe" T-stat since they permanently lock open if you ever over-heat.

mr. grissom ....

thank you for your input on the debate over the detriment of not using a thermostat in a vehicle. since i have been reading and posting thoughts here on FABO, you may be the first "bona fide" "engineer" to have responded to a post.

as i noted in my original remarks regarding suggestions for reducing the operating temperature of vintage V-8 motors, my personal experience from years ago supported the contention that removing a thermostat completely would lower the operating temperature of these engines. while science doesn't always support drawing conclusions simply based upon "observations", sometimes one can do that finding that there is a positive correlation between what is observed and what has actually happened. years ago (1960's-70's), it was a common practice in w.va. to remove the thermostat in an over-heating car in the summer - and that practice often DID solve the problem (unless there were other issues such as a warped head, rust in the water channels in the block, improper timing). however, in this thread, my "no thermostat" theory was quickly challenged. further, in my own research, i found (and posted) the above lengthly article from a commercial engine building shop that also concluded that removing a thermostat would cause the "water to flow too fast through the radiator to allow cooling." i find it somewhat amusing that the origin of this theory stems from a 1920's "observation" of an overheating car that led to the wrong "conclusion" as to the cause of that observation.

one thing that i did find helpful in the above article i posted was the number of variables that can contribute to the overheating problem of a running auto engine. just "removing" a thermostat may, in fact, NOT solve the problem. i for one never really considered the "cooling system" of a car to be either "that important" or "that complicated" - obviously, that is the WRONG assumption!!

thank you again for your imput...
 
I'm Not sure who jimharvard's snide remarks were intended for so I'm curious jimharvard, where did you get your degree? If your shot was at me, my degree came from Cal Poly 1972 not a slouch school. So beyond being able to capitalize and italicize what do you bring to the table?

BillGrissom, I didn't see where anyone said anything about water flowing too fast through a radiator, etc., and I certainly wouldn't challenge your expertise in heat transfer. Having said that though, I do know that if I don't use a thermostat in my sprint car to throttle coolant flow it doesn't perform as well.

And, I'm outta this thread.
 
I'm Not sure who jimharvard's snide remarks were intended for so I'm curious jimharvard, where did you get your degree? If your shot was at me, my degree came from Cal Poly 1972 not a slouch school. So beyond being able to capitalize and italicize what do you bring to the table?

BillGrissom, I didn't see where anyone said anything about water flowing too fast through a radiator, etc., and I certainly wouldn't challenge your expertise in heat transfer. Having said that though, I do know that if I don't use a thermostat in my sprint car to throttle coolant flow it doesn't perform as well.

And, I'm outta this thread.


mr. retroron...

well... i don't know how to respond to you other than to say i did not intend any "snide remarks" directed to you. i think when i offered my opinion on the effect of using and not using a thermostat i stated i would like to hear from other FABO members on this issue and that i didn't want any "angry responses." so if i've offended you retroron, i apologize.

i am not an engineer, i am an attorney. i did go to Harvard but i did not study any engineering classes there. i could have cross-enrolled in classes at MIT but my double major was Psychology and Government - not "the sciences" so i never did that. i have no doubt "Cal Poly" is an excellent school.

the only things "i bring to the table" here on FABO (other than the ocassional "lawyer stuff") is a lifetime of mechanical and body work on cars. i'm 63 now and got my first car at 15 - so about 48 years of "practical" experience. AND i started playing with mopars in high school (70-72).

my first opinion (from my personal experience) was that running without a thermostat would increase the cooling of a vintage V-8. then, after reading your post about that not being the case, i did some research and posted the above article that also agreed that running without a thermostat will not aid cooling. THEN bill grissom posted that "as an engineer" he knew that the idea of no thermostat causing water to flow too quickly through a radiator for cooling heat transfer to occur was "incorrect" and actually similar to an "old wives tail."

so there you are mr. retroron. i'm sorry i offended you. it seems that there is a reasonable disagreement on this thread as to the cooling effects of installing or not installing a thermostat in an old V-8. i don't know what else to say...
 
I too have taken the t-stat out sometimes they ran cooler but mostly ran hotter or even overheated. Now I have replaced thermostats on a 75 fury factory 318/904. This car always ran over half on the temp gauge which always bothered me. So I pulled the t stat 195 so I changed to a 160. It ran much hotter on the temp gauge then got into the max 20 miles down the road. Changed to a 180 a little better but not too much. Ended up putting a 195 back in and lived with it for many years . I always thought that mopars had a marginal cooling system and Fords had the most generous system. Kim
 
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