Okay, I have been inspired from some previous posts about "How can I gain more horsepower?"
I See people recomending turbo's, Pistions, Cams, yada yada yada. Yet I have yet to seen someone explain the vital improtance of the cooling system. So I am here to save the day with some info.
Let's start with some basic info:
Less than 40%
off the heat generated through combustion is turned into Horsepower (this term is called thermal efficency, now this is only applicable to a N/A vechile, if you are F/I this number will change drasticly anywhere from 50% - 200% almost 2x as much).
This means that 60%
of the heat occuring from this air fuel mixture is let out through your exhaust and through your cooling system.
Now lets start with the basic components of the cooling system are.
2. Fan (Electiric / Belt driven)
3. Water Pump
Now these are all equal in importance, no one is greater then the other.
Now lets check out the basic out the basic functions of these.
Radiator- Exchange the heat into the atmosphere in exchange for cold air. This is called a heat exchanger, Heat exchanger are devices where 2 or more moving fluids streams exhcange temperture. with out mixing.
Fan- The fan is an assistant in moving air toward the radiator accompanied by the fan shroud. Now in most cases the fan is an excessory item the reason I say this becuase most fans do not kick in at highway speeds on in the city becuase air movment is so great at high speeds so in theory you can basicly get rid of your fan at the track for weight saving, but be careful of the temperature and the number of passes you are making.
Water pump- Is like the heart, keeps the circulation
with out it you can will die.
Cap- To keep the system under a constant flow the cap keeps the system closed to the atmosphere, and also keep the system under a certian pressure.
Thermostat- A temperture controled valve allowing coolant to pass through to the radiator when hot to allow heat exchange and closed to allow for warm up when cold.
Hoses- Like the vesels keep everything connected.
Coolant- The carrier, that allows for all of this to happen.
When to upgrade radiators?
This question has baffled many of us. The basic guide line is if your vechile is making 10%
or less Horsepower then stock and you never really beat on your vechile you really don't need a upgrade. But if your radiator is more then 4 years old and you are generating about 20%
more power than stock or do and kind of track/ road racing you should consider and upgrade.
There are so many out there, which radiator to pick?
When choosing a radiator you must understand there are alot of factor that play apart of this process such as core lenght, width, thickness, tube thickness, tube spacing and fin density. Now I can't tell you exactly what to get becuase there isn't a basic guide for this. All I know is companys have spent thousand into research, and have designed certian radiators for certian applications for example a radiator designed for track is going to have a better cooling capacity then a drag. So call the companys and ask. But in general a equal balance of all the properties makes the best radiator.
Now updating fan?
If you are and elecritc fan which most of us are we really don't have any options for update unless there is a double electric fan some where out there that I am un aware of so keep it as it is or find a bigger fan.
For coolant to be able to carry heat it must remain in its' liquid form and not turn into a vapor this is very improtant.
Let us take into conciderator Boilng point. Pure water boils at 100 degrees celcuis
and freezes at 0 degrees celcius, this is all under normal atmposphere conditions. Now if we apply pressure to like 14.7 psi the water will not boil till 121 degrees Celsius, and when you install a 18.9 psi cap water Will not boil till 124 degrees celcuis.
Wait, but pressure is not the only important part of this, mixture is just as important. Ethylene-glycol AKA Antifreeze is a fluid that has chemical additives to prevent rust and to lubricate the water pump. Now using a mixture of water and anti-freeze has its advantages and disadvantages, Using a 33% solution will raise the boiling point 4 degrees celcius, and using a 50% solution will raise the boiling point 9 degrees celcius. But here's the bad Antifreeze does not have the same heat capacity as water it is actually 20% less. So a 50/50 mixture (1 quart) that passes through the system will only be able to carry 80% of the heat, while the pure water can take nearly all away. So this led to the sports world to use pure water and rust inhibitor and boosters that reduce surface tension.
In the bigger picture though when water freezes it increeses almost 9% in volume, and if this where to happen it could cause major harm in cold weather, but here's the saviour again, a 33% mixture will drop the freezing temperture to nearly 16 degrees celcius and a 50/50 mixture will drop the point to almost 37 degrees celcius.
So now I bet you're in a world of wonder of what to fill your car with?
First you must determine the lowest temperture you are going to encounter and then add the least amount of Ethylen-glycol in cordination with this, usally there is a chart for you to fallow on the back as a guideline. But if you are using less then 50/50 mixture please use the additives.
So in the end my friends don't forget to think about the cooling system, If you do be prepared for a multitude of problems.
Please feel free to comment, and add more
Modified by q45mm at 12:58 PM 2/16/2006
Modified by q45mm at 1:29 PM 2/16/2006