JamaicanEvo

I have an evo iv which i am building for circuit racing. After a couple laps my coolant temps reaches 230 degrees. I have a Magan aluminium radiator and spal fans. I just built the engine so i know the head gasket is good, the car is not pushing out any water. I took out my thermostat during the build. I am told that at high speed without the thermostat, the water does not have enough time to cool in the radiator and as such the car temps will rise. Can anyone advise me if this is in fact true or what they think the problems might be

JFuego777

iTrader: (8)

Yes this is completely true. Your thermostat is a vital component of your engine management system...it regulates the engine temp, which effects all sorts of things, a/f ratio, timing advance, boost, etc. Definitely always run a thermostat.

barneyb

I've heard this before. So, if the water goes too fast through the radiator to cool then shouldn't it go too fast through the engine to get hot?

I'm told, without the flow resistance of a thermostat, the water pump on some engines will cavitate. You could try a thermostat to see if it helps. Cavitation is only going to occur at high rpm. However, I suspect the cooling system, either fans or the radiator.

Murf

iTrader: (2)

Yes that can happen. T-stat makes a restriction that slows the coolant flow enough for heat to leave the coolant through the fins in the radiator.. This can also happen in cars with modded/ higher flow water pumps. ( friends 351 is doing that now).

sblvro

iTrader: (2)

I think taking out the thermostat is okay. it will take time to warm up the engine though because on start-up, coolant is flowing in the engine instead of being warmed-up and be in the closed-loop mode until operating temp oepns up the thermostat. because normally, in a fully warmed up engine, the themostat is open and stays open all the time.

MR. EVO MR

iTrader: (9)

Are u sure about that?
so how does the coolant get cool if it constantly circulates? Please let us all know your thinking.


edit: found this online----> http://autos.yahoo.com/maintain/repa...ques018_2.html

The thermostat's job is relatively simple, but extremely important. It regulates the engine's operating temperature. It does this by restricting the flow of coolant from the engine back to the radiator. The thermostat is usually located in a housing where the upper radiator hose is connected to the engine. The thermostat is a valve that is held shut by spring tension. A wax filled thermal element in the thermostat opens the valve. As the engine begins to warm up and the coolant gets hot, the wax inside the sealed element expands and pushes the thermostat valve open. This occurs at a preset temperature (typically 195 degrees F. or so), which is usually stamped on the thermostat itself. The thermostat should be fully open about 20 degrees F. above the rated temperature.

The opening of the thermostat allows coolant to circulate through the engine and cooling system. As the temperature of the coolant begins to drop, the wax element cools off and contracts allowing the thermostat to partially or fully close. Thus, by cycling open and shut a relatively constant operating temperature is maintained.


people like you giving bad and misleading information

MR. EVO MR

iTrader: (9)

here's another link--->
http://www.2carpros.com/how_does_it_...ostat_work.htm


If the thermostat is stuck open or broken it has failed and needs replacing. Never run an engine without a thermostat because the thermostat works as a system flow regulator as well. What this means is the thermostat has a specific opening that regulates the flow through the cooling system. If the coolant is allowed to flow too quickly through the radiator the coolant will not have time to transfer the heat it has absorbed. This will cause the engine to overheat.

sblvro

iTrader: (2)

the thermostat is not a switch that opens and close. like you mentioned, it is a wax element and has a specific temp to open. if you notice, there is no lower temp because it is closed at that time. what is the advantage of keeping it closed? the temp is regulated by the fan in your radiator to keep it within normal temp. the purpose of the OP is if he is going to use it in tracking, very hot conditions, what is the advantage of closing the thermostat? none whatsoever. did I give a bad or misleading info than what you have just repeated? no.

sblvro

iTrader: (2)

for racing purposes, it is okay to remove the thermostat!

http://www.racingbeat.com/Tech/Tech.Water.1.htm

1d10t

iTrader: (19)

You may be a good driver, but if you didnt know that removing the thermostat would make your car over heat, I suggest out sourcing a builder. Sorry to sound harsh, but there are countless mounds of information, that given the desire and ample intuitive, you can study. You can build a coolant restrictor in place of the t-stat, to slow the flow down.

JakeTheVIII

iTrader: (35)

Ok...so we've established that there's no downside to removing the thermostat on a car for racing, because it's constantly circulating coolant, which is the best possible scenario, right?

Now...Does the constant, full-time circulation restrict the ability of the coolant to be cooled down during it's passing through the radiator? If so, then this would not be ideal for racing, right? Someone enlighten me...

1d10t

iTrader: (19)

Im not quite sure what youre asking jake, but you dont want the coolant too hot, obviously, and the coolant being pushed through the radiator so fast that there is not sufficient time for heat to be transferred then you will overheat.
The thermostat has a wax pellet. Which expands at a certain temperature to open the coolant system and allow it to flow through.
With out the thermostat, it will take a long time to heat up ( no biggie ), but the water pump will flow too much with out the restriction of the thermostat.
Unrestricted flow may also cavitate, which can cause other damages

1d10t

iTrader: (19)

Althought, Im sure you know what youre doing. From reading your posts over the years

MR. EVO MR

iTrader: (9)

LOL aren't they talking about a rotary engine?

give me a sec im searching online if EVO's have rotary engines................

MR. EVO MR

iTrader: (9)

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Original Post:
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