Intercoolers...

Soldato
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19 Jan 2003
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What the hell do intercoolers do?

They look kinda rubbish but I'm sure they do something magical?

Can you get them on petrol engines? Or just diesels?

Sorry for the dumbness.

Chris
 
Yes, you can get them on both petrol and diesel engines.

When you're using a turbocharger it is compressing the incoming air. Basic thermodynamics causes the temperature of the air to rise, and as we all know this is bad for performance.

An intercooler is effectively an air-cooled matrix, that the compressed air from the turbo passes through before going into the engine. Air rushing over the radiator removes heat from the intake charge, cooling it down and increasing performance.

You can get water cooled and dry ice cooled intercoolers too, or spray them with a mist of water or N20 to reduce their temperature.

On average, the bigger the intercooler, the more chance you stand of dropping the intake air temperature more, allowing for higher performance (or more boost, if you're heating it up so much that performance is falling)


No need to apologise for the dumbness! Makes you look more sensible if you ask instead of rambling or being uncertain! Reminds me of the time when my mate spent half an hour lecturing some friends on how a DUMP VALVE was a section of the exhaust that got switched over when you changed gear, which made the noise :D....I laffed, and let him continue ;)
 
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Basically when you turbocharge an engine the air gets sucked in and compressed. This heats the air up to such a degree that it can actually reduce performance of the car.

This is because hot air does not combust as wel as cool air. An intercooler simply addresses this by allowing the hot air to run through a series of cooling metal fins which in turn cools down the air. It goes in one side hot and comes out the other side cool and then proceeds into the engine cylinders where it's burnt along with the fuel

Thats basically it, intercoolers are radiators for compressed air, but without them you wouldnt get high performance turbocharged cars.
 
I think they are there to put on your car if u have a turbo. Its to cool something down due to having a turbo.

If im wrong dont shoot me, i learnt that from Gran Turismo :D
 
Lashout_UK said:
You can get water cooled and dry ice cooled intercoolers too, or spray them with a mist of water or N20 to reduce their temperature.
isnt that called a charge cooler rather than intercooler? not sure on this just i thought that was the difference. Inter cooler being cooled by air and chargecooler being cooled by water/othermeans
 
Stonedofmoo said:
Basically when you turbocharge an engine the air gets sucked in and compressed. This heats the air up to such a degree that it can actually reduce performance of the car.

This is because hot air does not combust as wel as cool air. An intercooler simply addresses this by allowing the hot air to run through a series of cooling metal fins which in turn cools down the air. It goes in one side hot and comes out the other side cool and then proceeds into the engine cylinders where it's burnt along with the fuel

Thats basically it, intercoolers are radiators for compressed air, but without them you wouldnt get high performance turbocharged cars.

Not to mention, that some turbo's spin up to 150,000rpm and can get red/orange hot, this also increases the intake temperature a lot.

In a little more depth, colder air is more dense than hot air and thus cooler air allows more air to be put into the cylinder which in turns allows for more fuel and a much more efficient combustion.

Intercoolers as mentioned, cool the air down by various methods before it enters the cylinders.

/EDIT It's nice to see that such a question can be asked on these forums without ridiculing the OP for not knowing, happens all too often on other owners club/car forums. Everybody has to start somewhere so kudos guys :)
 
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150k RPM

JESUS!

I know a bit about mechanics, infact I am pretty good with the entire car but do not know engines and gearboxes in great detail. Cheers.
 
yeah i know its not relative to cars but i used to work with turbo vacuum pumps in my old job, and if one of the blades was out of balence or one broke while in operation the whole thing would just disintigrate at those speeds.
 
but of a random question and I have no idea about these things but doesnt the air going through the intercooler have greater resistance and the pressure get reduced?
 
Charge cooling is similar. The air runs through a special waterjacket which cools the air as it runs through, same as an intercooler.

The difference is the water then itself asorbs the heat so that in turn is pumped around to a seperate water radiator which has airfow running over it and this cools the water.

This is used more often on mid engined cars where pipework of running an intercooler to the front of the car would be far less efficient than running a chargecooler system.
 
JamesM said:
but of a random question and I have no idea about these things but doesnt the air going through the intercooler have greater resistance and the pressure get reduced?

Yes, but with a good design only by 1 or 2 psi.
 
JamesM said:
but of a random question and I have no idea about these things but doesnt the air going through the intercooler have greater resistance and the pressure get reduced?

Yeah they do, intercooler efficiency will affect the size of the core you need. More efficient cores can be smaller, howevere they tend to cause more turbulance which causes pressure losses across the core. So for example you may want to run at 14psi at the engine, an intercooler with a 2psi pressure loss will mean the turbo is working harder as it has to make 16psi. This will increase air temps before the cooler.

Again if you have a nice free flowing massive intercooler, great for top end power too as the air can pass through easily then you can promote throttle lag as there is more volume to pressurise.

Selecting the correct intercooler depends on a lot of this factors and biggest isn't always best
 
They're all charge coolers. As they all cool the air charge :) Air-Air are more commonly known as Intercoolers. Air-Water ones are more efficient at cooling the air, but can saturate quicker if the water tank isn't big enough. Saturation = the cooling medium itself is at such a temperature it can't remove sufficient heat from the charge air to make a difference.
 
Cold air is denser than hot.

Edit: In simple terms:

Normal Air -> Intercooler -> Cold air (more in same volume) -> More air to combustion chamber than normal -> more energy + better combustion of fuel = More performance.

:)
 
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Cant remember the exact figures, but I think, and please dont quote me but the principle stands, that for every 10C you drop the intake temperature, you can obtain a 10bhp increase in performance, so 1:1 IIRC
 
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