Is 160 degree thermostat
#1
Pro
Thread Starter
Is 160 degree thermostat
really any better than stock thermostat?
#2
Melting Slicks
Member Since: May 2005
Location: Stuttgart
Posts: 2,039
Likes: 0
Received 0 Likes
on
0 Posts
160 is a little cold for my liking. The whole idea is to keep the air density as high as possible (more air more power). Higher temps start the cat sooner and get rid of residual water sooner - good things! Lowering the engine temp will slightly increase the air density. The standard intake and air flow has not been identified as key limitation for the stock LS2 so I doubt that the thermostat temp will make much of a difference.
Last edited by Steve Germany; 02-16-2006 at 03:11 PM.
#3
Racer
Member Since: Jul 2003
Location: sterlling heights MI
Posts: 281
Likes: 0
Received 0 Likes
on
0 Posts
I agree
Seems like when cars overheated in the summer putting in a lower temperature thermostat would keep you out of problems. I haven't run into that issue since C3s.
#4
Team Owner
160
I am not putting one in because I heard a while ago it turns the oil to sludge in a hurry!True or not,i don't think there's much to gain putting one in.As a matter of fact,MY CAR IS FRIGGIN PERFECT AS IT IS!!! Tha *** end always wants to slide sideways or something when i punch it!!
#5
Originally Posted by rmp
really any better than stock thermostat?
one of the best thing you can do for your c6...don't know any one that is making at lease 50 hp more than stock without one. colder air = more oxygen module = more hp/tq.
#6
Intermediate
True colder air has more air molecules. 160 degree air has 4.9% more air molecules in it than 190 degree air at the same pressure. But how does the coolant cool or heat the incoming air or does it? Even if it does get cooled in order to take advantage of the denser air, more fuel is needed to get more power or you'll go lean. Since the mass flow sensor is located in the throttle body, the fuel is adjusted based on the air density before it is cooled or heated by the 160 or 190 degree coolant.
Does anybody have any conclusive data? Like dyno results before and after a thermostat change?
Does anybody have any conclusive data? Like dyno results before and after a thermostat change?
#7
Originally Posted by Harold Wilson
True colder air has more air molecules. 160 degree air has 4.9% more air molecules in it than 190 degree air at the same pressure. But how does the coolant cool or heat the incoming air or does it? Even if it does get cooled in order to take advantage of the denser air, more fuel is needed to get more power or you'll go lean. Since the mass flow sensor is located in the throttle body, the fuel is adjusted based on the air density before it is cooled or heated by the 160 or 190 degree coolant.
Does anybody have any conclusive data? Like dyno results before and after a thermostat change?
Does anybody have any conclusive data? Like dyno results before and after a thermostat change?
Last edited by cbrf4i1; 02-17-2006 at 01:21 AM.
#8
Team Owner
Originally Posted by jesse12804
I am not putting one in because I heard a while ago it turns the oil to sludge in a hurry! True or not
Originally Posted by cbrf4i1
one of the best thing you can do for your c6...don't know any one that is making at lease 50 hp more than stock without one. colder air = more oxygen module = more hp/tq.
Also don't forget that it's not just the 160* thermostat by itself that helps, ine must also have their fan settings adjusted (LS2 Edit/HP Tuners etc.) accordingly as well.
A company such as Cartek (www.cartek.net) can help with this and other mods.
#9
Originally Posted by jesse12804
I am not putting one in because I heard a while ago it turns the oil to sludge in a hurry!True or not,i don't think there's much to gain putting one in.As a matter of fact,MY CAR IS FRIGGIN PERFECT AS IT IS!!! Tha *** end always wants to slide sideways or something when i punch it!!
The longer warm up time does mean it'll take a couple minutes longer from a cold start for the oil to heat up enough so it is safe to get on the car hard. It also means a couple more minutes before the heater will do you any good.
The thing you have to understand is that the engine will stabilize at a temperature that's a function of load and cooling capacity. Cooling capacity is fixed by the size of the radiator and the airflow through it. Engine load is demand based, of course, so the harder you drive, the more heat the cooling system has to reject to achieve equilibrium.
The thermostat doesn't have any role in this after it opens. It doesn't matter if it opens at 160 degrees or 187 degrees, the stock engine is going to reach an equilibrium temperature in the mid-190s at light loads and high airflows, and the equilibrium temperature will be on the order of 230 degrees at very high loads or low airflows. This is the result of design decisions Chevy made when they sized the radiator and the opening through which it receives cooling air. (Also when the fan kicks on if you aren't moving.)
To materially change the equilibrium temperature, you'd have to increase the size of the radiator, increase airflow through it, or reduce engine demand. Since the latter isn't a performance goal, a bigger radiator or more airflow are the only ways to get engine temperatures down from the stock equilibrium points. Changing thermostats, or even removing the thermostat entirely, won't change the equilibrium temperature.
Now it is certainly true that cold air is denser than hot air. Denser air means more oxygen can get into the engine on each intake stroke, which means you can burn more fuel, and thus make more power. This is why cold air induction systems work. It is a (very) minor form of supercharging.
Ok, fine, cold air is good, but how much will the engine's coolant temperature affect intake air temperature. With cold air induction, the answer is practically not at all. At 6000 RPM, any given cylinder full of air only spends 2 hundredths of a second in the engine (from air cleaner to tailpipe). Very little heat can be transferred to the intake air by conduction or radiation from the intake manifold in such a short time. IAT readings show this.
The rate of heat flow is a function of the difference in temperature between source and sink. Most of the heat transfer to intake air occurs at the intake valve, which runs much hotter than engine coolant because it is in direct contact with combustion gases. Changing coolant temperature by a few degrees won't materially change the high temperature of the valve head.
So lowering the engine coolant temperature won't materially affect intake air temperature unless the air is being drawn from the engine compartment, where it has dwelled long enough to pick up significant amounts of heat.
#10
Originally Posted by shopdog
The thermostat doesn't have any role in this after it opens. It doesn't matter if it opens at 160 degrees or 187 degrees, the stock engine is going to reach an equilibrium temperature in the mid-190s at light loads and high airflows, and the equilibrium temperature will be on the order of 230 degrees at very high loads or low airflows. This is the result of design decisions Chevy made when they sized the radiator and the opening through which it receives cooling air. (Also when the fan kicks on if you aren't moving.)
Last edited by cbrf4i1; 02-17-2006 at 04:56 PM.
#11
Burning Brakes
Originally Posted by jesse12804
I am not putting one in because I heard a while ago it turns the oil to sludge in a hurry!True or not,i don't think there's much to gain putting one in.As a matter of fact,MY CAR IS FRIGGIN PERFECT AS IT IS!!! Tha *** end always wants to slide sideways or something when i punch it!!
#12
Originally Posted by shopdog
Ok, fine, cold air is good, but how much will the engine's coolant temperature affect intake air temperature. With cold air induction, the answer is practically not at all. At 6000 RPM, any given cylinder full of air only spends 2 hundredths of a second in the engine (from air cleaner to tailpipe). Very little heat can be transferred to the intake air by conduction or radiation from the intake manifold in such a short time. IAT readings show this.
The rate of heat flow is a function of the difference in temperature between source and sink. Most of the heat transfer to intake air occurs at the intake valve, which runs much hotter than engine coolant because it is in direct contact with combustion gases. Changing coolant temperature by a few degrees won't materially change the high temperature of the valve head.
So lowering the engine coolant temperature won't materially affect intake air temperature unless the air is being drawn from the engine compartment, where it has dwelled long enough to pick up significant amounts of heat.
The rate of heat flow is a function of the difference in temperature between source and sink. Most of the heat transfer to intake air occurs at the intake valve, which runs much hotter than engine coolant because it is in direct contact with combustion gases. Changing coolant temperature by a few degrees won't materially change the high temperature of the valve head.
So lowering the engine coolant temperature won't materially affect intake air temperature unless the air is being drawn from the engine compartment, where it has dwelled long enough to pick up significant amounts of heat.
higher stat will have higher underhood temperature, where does the air filter get the air from (unless you have a bottom feeder, of course)? oh yeah, under the hood....sounds like the stock car guys / gals don't want your car to be any faster............
Last edited by cbrf4i1; 02-17-2006 at 05:55 AM.
#13
Pro
Thread Starter
Very erudite responses!
I guess what concerns me is why GM just didn't install the 160 degree thermostat in the first place if it was beneficial to performance; there must be some down side, ?emissions???
#14
Originally Posted by rmp
I guess what concerns me is why GM just didn't install the 160 degree thermostat in the first place if it was beneficial to performance; there must be some down side, ?emissions???
Last edited by cbrf4i1; 02-17-2006 at 01:55 PM.