Thermostat trick...?

[roger longman]

Hi all, I'm still not convinced. An engine has a specific temperature at which all components are happy. I am of course refering to street cars not dragsters and similar. This temperature is the medium at which longevity and performance coincide. As there are still many variances on either side of this argument. Could anyone come in with specific technical points not quarter mile times and speed ? I wouldn't be happy running mine in Los Angeles (temp today 74 F) at 30 degrees lower. Roger.

 

[joshwilson3]

Hi all, I'm still not convinced. An engine has a specific temperature at which all components are happy. I am of course refering to street cars not dragsters and similar. This temperature is the medium at which longevity and performance coincide. As there are still many variances on either side of this argument. Could anyone come in with specific technical points not quarter mile times and speed ? I wouldn't be happy running mine in Los Angeles (temp today 74 F) at 30 degrees lower. Roger.

I'd just run a stock temp stat. Though the 195 Robertshaw I put in seems to open sooner than an OEM style 195 stat. So, it runs cooler, which could help prevent a head gasket problem by keeping temps down while I'm driving around town. As the L98's are known for headgasket failures.

Though, I wouldn't put a 160 stat in.

 

[jonszr1]

roger all i can tell you is if you dont believe after all that has been written maybe do a google search and get some more data.the wonderfull thing about the car hobby is the ONLY person that has to be happy is you. everyone has their own opinions . i will run my cars at what ever temp i deem best and could care less what anyone else thinks about it . unless they buy me the car ,pay for ins,gas and any other expensis may occur . so if you dont feel comfortable running a lower temp therm no biggie, remember the only person you need to make happy is yourself and thats the bottem line ,.have a great new year

 

[jonszr1]

if yoy are worried about the temps going up around town you can do 2 things to help keep them down .either have your prom redone so the fans go on sooner .stk they go on first fan 223 and second fan 230. any tuner can change them for you or install a toggle switch to turn the faqns on any time you want . i use this setup to keep the temps down in the staging lanes . also the robert shaw is the best therm around .

 

[joshwilson3]

if yoy are worried about the temps going up around town you can do 2 things to help keep them down .either have your prom redone so the fans go on sooner .stk they go on first fan 223 and second fan 230. any tuner can change them for you or install a toggle switch to turn the faqns on any time you want . i use this setup to keep the temps down in the staging lanes . also the robert shaw is the best therm around .

The one thing about the Robertshaw is the 195 acts like a 180. I've got a 195 Robertshaw and I see temps running around town at 175-180. They should be closer to 195.

I did have to drill a small hole at the top of the center shaft. As when I dunked the Robertshaw, I noticed alot of air would get trapped under that shaft. So, I drilled a small hole to let that air pass. That is one way a thermostat can not work as designed is when air gets trapped behind it.

 

[bucket]

Hi all, I'm still not convinced. An engine has a specific temperature at which all components are happy. I am of course refering to street cars not dragsters and similar. This temperature is the medium at which longevity and performance coincide. As there are still many variances on either side of this argument. Could anyone come in with specific technical points not quarter mile times and speed ? I wouldn't be happy running mine in Los Angeles (temp today 74 F) at 30 degrees lower. Roger.

......
hey Roger,
i am in los angeles also, over by the tar pit..
i didnt like last summer...running at 204..the AC just wasnt cold enough....
and i had to put my solid top on to keep from being in a convection oven..
i bought a hypertech 160 on ebay and got it the next day..
i pondered all the responses here and today, i did the deed...
i aint lookin back

 

[joshwilson3]

......
hey Roger,
i am in los angeles also, over by the tar pit..
i didnt like last summer...running at 204..the AC just wasnt cold enough....
and i had to put my solid top on to keep from being in a convection oven..
i bought a hypertech 160 on ebay and got it the next day..
i pondered all the responses here and today, i did the deed...
i aint lookin back

So, how is running a lower stat going to keep it cooler inside the car??

 

[bucket]

if yoy are worried about the temps going up around town you can do 2 things to help keep them down .either have your prom redone so the fans go on sooner .stk they go on first fan 223 and second fan 230. any tuner can change them for you or install a toggle switch to turn the faqns on any time you want . i use this setup to keep the temps down in the staging lanes . also the robert shaw is the best therm around .

....

the fan alone doesnt do much..
i did that first

 

[bucket]

So, how is running a lower stat going to keep it cooler inside the car??

if the radiator is cooler the condenser will be cooler...

 

[joshwilson3]

if the radiator is cooler the condenser will be cooler...

Ok, but never have heard that before. I know the air hits the condensor before it hits the radiator.

 

[bucket]

Ok, but never have heard that before. I know the air hits the condensor before it hits the radiator.

yes...your right

 

[helphos]

Any Scientists in the group?

One of the questions I'd like to know is 'what temperature will your Vette run at with no thermostat? (Let's ignore such variables as speed and ambient air temperature, for now- maybe assume 72 degrees and stuck in traffic (5mph)).

If the answer is anything over 190, then I'd say that the difference between 160 and 185 is negligible, because after 15 minutes all thermostats will be wide open (agree or not on wide open?).
As with the other well thought out posts here, there will be exceptions like drag racing, etc., and everything is subject to personal tastes.

Perhaps in cold climates the stat would make a bigger difference?

This would make a great science fair project for one of our kids!!

 

[joshwilson3]

One of the questions I'd like to know is 'what temperature will your Vette run at with no thermostat? (Let's ignore such variables as speed and ambient air temperature, for now- maybe assume 72 degrees and stuck in traffic (5mph)).

If the answer is anything over 190, then I'd say that the difference between 160 and 185 is negligible, because after 15 minutes all thermostats will be wide open (agree or not on wide open?).
As with the other well thought out posts here, there will be exceptions like drag racing, etc., and everything is subject to personal tastes.

Perhaps in cold climates the stat would make a bigger difference?

This would make a great science fair project for one of our kids!!

Don't know. But if I sit idle with the heat/ac OFF, then I go to the 230 or whatever the fans kick on. If I sit at idle with the heat/ac ON, then I tend to stay around 200.

With my 195 Robertshaw stat, driving around town, I'm at 175-180. So, I say it is possible if you have a 160 stat to run at 160 or below driving around town.

I know when I first got my vette, the temps stayed around 150-160 driving around town. I put a new stat in, and the temps went up to the 195. A year later is when I put in the Robertshaw stat.

 

[helphos]

Thanks!

That's good to know. I wouldn't have thought the radiator was that efficient.
Very good information!

 

[joshwilson3]

Thanks!

That's good to know. I wouldn't have thought the radiator was that efficient.
Very good information!

Yeah, and I'm betting its old too. I had noticed a brown film inside on the fins when you look in the radiator cap hole.

I had noticed the upper and lower radiator hoses were original. So, I recently replaced them with GM hoses. I also recently flushed the engine with distilled water. And filled with Zerex G-05 antifreeze.

The good thing as well is this is an indication the head gaskets are still good.

 

[bucket]

mine ran 220, that freaked me out...

 

[Curious George]

One of the questions I'd like to know is 'what temperature will your Vette run at with no thermostat? (Let's ignore such variables as speed and ambient air temperature, for now- maybe assume 72 degrees and stuck in traffic (5mph).

From what I understand, taking the thermostat out may actually lead the vehicle to overheat. This is due to the fact that the water is circulating through the system too fast and not absorbing heat. A thermostat also regulates the flow (speed) of water and this helps the water absorb heat as it circulates. The temp gauge and computer may not register the overheating, (because the sensors are in the flow of water) but the engine will certainly know.

CG

 

[bucket]

From what I understand, taking the thermostat out may actually lead the vehicle to overheat. This is due to the fact that the water is circulating through the system too fast and not absorbing heat. A thermostat also regulates the flow (speed) of water and this helps the water absorb heat as it circulates. The temp gauge and computer may not register the overheating, (because the sensors are in the flow of water) but the engine will certainly know.

CG

....
this is true...
the system pumps way too fast to ever cool off in the radiator and will run hotter

 

[joshwilson3]

....
this is true...
the system pumps way too fast to ever cool off in the radiator and will run hotter

"A common misconception is that if coolant flows too quickly through the system, that it will not have time to cool properly. However the cooling system is a closed loop, so if you are keeping the coolant in the radiator longer to allow it to cool, you are also allowing it to stay in the engine longer, which increases coolant temperatures. Coolant in the engine will actually boil away from critical heat areas within the cooling system if not forced through the cooling system at a sufficiently high velocity. This situation is a common cause of so-called "hot spots", which can lead to failures.

Years ago, cars used low pressure radiator caps with upright-style radiators. At high RPM, the water pump pressure would overcome the radiator cap's rating and force coolant out, resulting in an overheated engine. Many enthusiasts mistakenly believed that these situations were caused because the coolant was flowing through the radiator so quickly, that it did not have time to cool. Using restrictors or slowing water pump speed prevented the coolant from being forced out, and allowed the engine to run cooler. However, cars built in the past thirty years have used cross flow radiators that position the radiator cap on the low pressure (suction) side of the system. This type of system does not subject the radiator cap to pressure from the water pump, so it benefits from maximizing coolant flow, not restricting it."

Source:

Stewart Components - High Performance Automotive Cooling

 

[gmjunkie]

From what I understand, taking the thermostat out may actually lead the vehicle to overheat. This is due to the fact that the water is circulating through the system too fast and not absorbing heat. A thermostat also regulates the flow (speed) of water and this helps the water absorb heat as it circulates. The temp gauge and computer may not register the overheating, (because the sensors are in the flow of water) but the engine will certainly know.

CG

Sure will over heat,but I don't know about because it's circulating too fast!! LT1/LT4's If you take a good look at the thermostat,It's also not only a Thermostat it's a internal by pass valve too!! If you leave the thermostat out, at higher RPM it WILL over heat!!hnoeshnoeshnoes Most of the coolant will by-pass the radiator all together!!