In central Texas, it is 100*+ in the summer and a low of ~50* in the winter. I have been racking my brain trying to figure out how to get the temps down in my car and thought, why even have a t-stat? Seeing that I only use the car with the top down and my computer is tuned to turn on the fans at 160*, isn't it just a bottleneck in the coolant flow?

A litte background - I have a Darton sleaved LS2 9:1 forged 427ci engine with an F1C, 243 heads running 11.5# boost.

After doing some searches, I came across Evan's coolant, so I gave them a call. The tech I spoke to agreed that I should remove the thermostat, block off the bypass, run NPG-R coolanth and recommended adding a ball valve in the heater circuit (5/8" line off the water pump) as well, just in case I want to use the car's heater at a later date.

 

I would think that after about an hour or so it would start to over heat. It would never have time to sit in the radiator and cool off.

 

bottleneck in coolant flow yes, but you somehow need to regulate the flow of coolant and allow it time in the radiator so heat exchange can take place, heat from coolant of 200+ to surrounding air < 120F. look at the cooling system as a whole, the size of the radiator and airflow through the radiator and out of the engine compartment will have the most significant affect. The greater the temp difference of coolant to air, the smaller the radiator, less airflow, and less time you'll need for adequate heat exchange to happen to maintain a given operating temp. In your case, if you want a 160F operating temp and surrounding air is 100F, you'll need a lot of coolant capacity and airflow to maintain that temp and I don't see that as being practically possible for a f-body.
you can also look into the heat exchange properties of the coolant, specific heat i think it is. but last i knew water was king and everything else will transfer heat worse than water. I would be weary of evans or anyone telling you something because they are going to be biased or ignorant and just want to sell you their product.
I looked at this, http://www.evanscooling.com/main25.htm
they take quite a lot of liberties pimping their product, of course there's the increases fuel economy and power (which is a contradiction) but reduces emissions and engine noise? Did they design the coolant to be burned in the combustion chamber, or do they think that happening isn't a problem that supercedes the coolant has anything to do with?
forgot to say, propylene glycol (evans) may have better heat transfer properties than ethylene glycol but that depends at what mix ratio of ethyl. glycol to water you use. You may easily be able to get better heat transfer of 70% water to 30% dexcool and a $10 bottle of water wetter vs whatever it costs for 3 gallons of evans coolant, and you'd also have to factor in completely draining your cooling system or the possible mixin g of old coolant with the new.

 

If there's always STEAMING hot water in the radiator, won't the radiator disperse more heat (as compared to having hot water and slightly cooler water) because the deltaT is larger? Bigger deltaT means higher transfer of energy, right?

 

I think their (Evans) argument is that since their coolant boils at a higher temp there is less steam in the system, thus, more liquid to metal contact and reduction in hot spots. They describe hot spots near / around the combustion area causing pre-detonation / vaporization, where that does not occur with the Evans coolant.

 

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I'm no expert. All I know, with my BBC, after pulling 160* therm, it ran much cooler. I also never ran below 60*.
I also read an article saying the old wives tail of keeping the water in radiator longer is better was bull.
I run a 160 GPH pump on my stuff. My stuff flows fast, especially compared to the 55 GPH pumps and it stays cool with 1000HP+.

John, my 2 cents. Test, every combination is different. Mark off a course, run with & without.
Start with same heat in the engine. Post up results. Good luck.

Like I said, I'm no expert, but with bigger pump & no therm, mine ran cooler.

.

 

From what I understand is that if you remove your thermostat your car will over heat. The coolant is flowing past the cylinder walls and heads and doesn't have enough time to remove heat from that area. The motor will over heat and seize because heat extraction hasn't taken place. It will do this even though you water temp reads low becaue it is not able to remove the heat from the motor. The thermostat also acts as a restrictor slowing the fluid velocity so heat exchange can take place.

 

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Forgot to mention, the article doing the test took readings from 10-12 locations on heads & engine,
just to prove their point.

If my heads were actually overheating, I would know by ET & between round maintenance.
My valve covers come off every pass. I've made a pass or 2. I would know, trust me.
Free flow & more GPH have sure worked for me. I doubt I've just been lucky, 5-6 engines in a row.

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I have pulled the thermostat out of engines before and I have never had one over heat. I had a thermostat stick open one time and the engine ran so cool that it was barely warm to the touch. A couple weeks ago we pulled the thermostat out of my friends boat that was running a little hot. Now it runs about 30* cooler on the gauge and the engine isnt as hot to the touch.

I'd say test it out for yourself. Anything you hear anymore is mostly hearsay. Use temp gun to measure temp on the engine somewhere (side of the block) before and after. Or you could drill a few holes around the edge of your thermostat. That will get it running a little cooler.

 

i run water wetter with straight water and it works way better than 50/50 mix

 

"It will do this even though you water temp reads low because it is not able to remove the heat from the motor."-----if the water is not pulling heat out of the motor than the engine temp will rise causing the temp gauge to read hot right? isnt that the whole point of having a temp gauge? please correct me if im wrong i just thought thats how it worked.

ive run without thermostats in both the 87 silverado(stock 305tbi) and 85 blazer(headers, dual 2.5"flows, edelbrock single plain mani, tow cam,750cfm double pumper) i used to dd. took the thermostat out of both of them when they went bad and the engine 1.ran cooler 2.took longer to warm to operating temp 3.ran cooler enough to make the heater not as hot. im not sure if the lsx's cooling systems are any different but experience(1gen sbc) says no thermostat=cooler temp.

 

[QUOTE=chevrunner21;9682362]"It will do this even though you water temp reads low because it is not able to remove the heat from the motor."-----if the water is not pulling heat out of the motor than the engine temp will rise causing the temp gauge to read hot right? isnt that the whole point of having a temp gauge? please correct me if im wrong i just thought thats how it worked.

QUOTE]

This is from what I understand about engines and what Ive learned through out the years. The reason for a temp gauge is yes to read hot. But the gauge measures coolant temp and not the temp of the heads or motor. The temp gauge mesures how hot the coolant is and i think jordan s. has a good idea on using a temp gauge for before and after to compare readings. Now I maybe wrong or some people have gotten really lucky. Just my $0.02

 

Keep the thermostat. Yes, your car would run cooler. But I doubt you would notice any gains power-wise. And I personally would be afraid of damaging engine components from lack of proper warm-up. Do you start your car in the morning and floor it? No. Unless your car is track-only I would leave it alone. Run a summer mix and try to worry about the bigger stuff.



If your car is overheating because you removed your thermostat then you have a MAJOR problem. Removing a thermostat from your car will do anything but make it overheat. Malfunctioning thermostats do one of two things. They either keep open, or keep closed. It's the latter that causes your car to overheat as it shuts off your engines coolant from flowing through the radiator after engine warmup. You're close on the last part. The thermostat does act as a restrictor to a point-It opens and closes based on trying to do one job-Keeping optimal engine temperature. Beyond that having too free-flowing system it's going to make your heads overheat because as long as there is constant pressure in the system (which is why air bubbles are bad) there will ALWAYS be heat transfer.

 

I Can Say From First Hand Expirence Ditching The T-stat Helps Alot...

Im In Fl And Its 90+ Here Most Of The Year.. When I Did My H\c Combo My Ect Was 220+ With A 160 T-stat And 160deg Fan Settings.. When I Pulled The T-stat It Dropped My Coolant Temps 20+ Deg

My Car Still Got Up To Heat Just Fine (little Slower But Not Much) And The Only Time I Had A Over Cooling Issue Was On A Long Wintertime Hwy Trip Where My Motor Did Go Down To A Ect Of 150

I Dont Know If I Picked Up Any Power But Id Have To Believe The Heatsoak Of City Driving Was Definately Causing Some Sort Of Power Loss


In The End Its Easy To Try And If Youtr Driving Conditions Matched Mine It Will Help

 

Btw I Had Like 5 T-stars And 2 Water Pumps Before I Opted To Take This Route

 

I echo the posters who said the coolant needs to "sit" in the radiator to shed heat. If it is constantly circulating (no T-stat) it does not shed as much heat as it would during (normal) cycling between the radiator and the engine.

To those who are running successfully without a T-stat, kudos to you... but I have always understood that under normal street-driven conditions the coolant needs some time in the radiator. The only guys I knew who ran without T-stats were pretty much full drag cars that got trailered to and from the track.

Another note: I am using "Hyperlube" brand additive in my Procharged '02 Z28. Previously it had suffered from the insufficient fan that ATI provides. I could not run the AC on 90+ days... exactly when I most wanted to run it... or the coolant temps would rise way too far. I tried Redline Water Wetter and it seemed to make little difference. I put in the Hyperlube brand that I picked up at Pep Boys and it totally solved the problem. Now my coolant stays at about 200-205 even running the AC on the hottest Saturdays that we have had this summer thus far. I am sold on it.

 

The myth that the coolant needs to sit still to absorb heat probably has a lot more to do with the fact that the only people who removed the thermostat were ALREADY having cooling issues.

 

The myth about needing to let the coolant sit in the radiator and cool down is absolutely false.

Heat transfer is driven my a difference in temperature. As the temperature inside and outside the radiator get closer, less heat energy is transfered per unit time. Also, the temperature of the coolant in the engine is getting higher, impeding the transfer of heat from the engine to the coolant.

When the thermostat opens, the much cooler coolant in the radiator moves into the engine, and the much warmer coolant from the engine enters the radiator. During this phase of heat transfer, the larger temperature differentials means that more heat energy is being transfered per unit time.

Unfortunately you don't gain anything. The increase in efficiency during the time that the temperature differentials are large don't make up for the loss of efficiency during the time that the temperature differentials are small. The amount of heat transfered for different temperature differences is not linear. You end up losing more than you gain.

More heat energy will be transfered to the ambient air if the flow is unrestricted.

But honestly, why are you even using anti-freeze in your coolant system if the temperature never gets below 30F? The specific heat capacity of good old H2O is nearly twice that of ethylene glycol. Just make sure you toss in a bottle of water pump lube to prevent corrosion and keep the pump seals nice and happy.

Of course you could use ammonia in your coolant as it transfers heat better than water... but then you would have to pressurize your coolant system to a few thousand psi seeing as ammonia boils at -30F.

 

Nope. As others have stated, fill a hot engine with water and run water through it in a constant loop. You are saying that I can circulate water through an engine fast enough to avoid heating it up. If you keep running water (the same water) through a 250 degree engine, you will wind up with 250 degree water. It does get hot in the block, and it gets cool in the radiator.

I'm running a custom built AFCO racing radiator with a built in oil cooler (and an Edelbrock water pump). I was having air flow problems at Nashville Super Speedway last year (running the road course) and called AFCO. I was told to remove the thermostat. I did and the car was better. With a 180 thermostat in the car, it would start to overheat in about 8-10 minutes of track time (overheat = 240 degree coolant temps on the autometer ultra lite mechanical gauge). With no thermostat, I'd get about 20 to 22 minutes on track before reaching the same temps.

The car absolutely exchanged more heat without a thermostat. Without a thermostat on the street, the car ran about 180 degrees on the freeway (75 mph). Once I fixed the airflow through the radiator, it sat on the pin at 140 on the autometer gauge, it just wouldn't make enough heat. I wound up putting a high flow 180 degree thermostat back in the car to warm it up.

 

+1

Have you ever worked with industrial cooling systems? I do it for living and I NEVER saw a system that cools better because the fluid sits longer in a hear exchanger. This is just against every thermal exchange rule and a basic common sense, too.