intercooling and engine temperature

[spereira]

hi
by installing an intercooler (diesel engine) the intake will be colder. This is obvious. Now, people tell me that because of this, the engine will run colder, also. But, the question is by installing the IC more fuel will be burnt, thus increasing combustion temperature since more heat will be generated (unless the cooling system is able to remove this extra heat) how can the engine run colder?? the heat generated by fuel combustion is much higher then the heat removed in the intake stream (sensible heat,only) Am I forgetting something? I'm asking this because I've been advised to install an IC to decrease the cooling fluid temperature and I don't see how this would work
regards
SPereira

 

[patprimmer]

I am only speculating here, but it seemsto me that if you don't put in extra fuel and don't pump a greater mass of air (to match the fuel), the coolant temp might go down slightly, but I expect that if you turn up the boost to the max it will take after intercooling, you will raise the coolant temp.

Regards
pat

 

[aorangi]

Coolant temperature is a cooling system problem. Perhaps a malfunctioning thermostat, clogged radiator, defective water pump or fan thermocontact. An Intercooler will reduce the whole thermodynamic cycle temperatures and engine thermal load as long as you still inject the same amount of fuel. But since you'll get a cooler and denser intake charge, you'll be able to inject more fuel for the same thermal load.

Cheers
Aorangi

 

[Chumley]

Hummm. When I play tennis, "people" tell me that if I hit the ball harder it will be harder to return and I will win more points. So, I bought a bigger racquet. Now, I hit the ball harder, except many times that I hit the ball harder, it flies out of the court and my opponent scores even more points against me.

How could that be?

Hope this helps!

Chumley

 

[JonMoon]

Hi People
I'm also thinking about installing an IC into my pick up (3l TD), a few points and questions (apart from the increase in Power and torque):
*If an IC does reduce the intake air temperature, then it must follow that if the same amount of fuel is being delivered (at a certain throttle opening), the engine must be operate at a lower temperature?
*A common mistake that is made is that people think that an IC will solve overheating problems (I learn't the hard way - blocked raidiator caused a blown gasket)
* The conversion that I have looked at (

http://www.steves.co.za

- IC for a Toyota KZ-TE) also includes a chip that is supposed optimise the tuning (specifically for the engine that is involved) - does anybody have any experience with this sort of system?
*Will a larger squash racquet help?
Regards

 

[spereira]

But since you'll get a cooler and denser intake charge, you'll be able to inject more fuel for the same thermal load
aorangi, the thermal load changes if you inject more fuel...right? and I have a feeling it will increase more than the sensible heat you've manage to remove by cooling the air down.

Chumley, I'm still recovering from you've just wrote ;-)!! I gather you agree that an IC will increase engine temperature??

*If an IC does reduce the intake air temperature, then it must follow that if the same amount of fuel is being delivered (at a certain throttle opening), the engine must be operate at a lower temperature?

that's correct, but the MAF sensor will detect a higher mass air flow so the ECU will increase fuel injection proportionally in order to compensate for the extra air drawn into the engine. otherwise it can decrease combustion efficiency (too much air is also damaging)

*A common mistake that is made is that people think that an IC will solve overheating problems (I learn't the hard way - blocked raidiator caused a blown gasket)

my thoughts exactely, but I can't seem to convince "people" of that...

* The conversion that I have looked at (

http://www.steves.co.za

- IC for a Toyota KZ-TE) also includes a chip that is supposed optimise the tuning (specifically for the engine that is involved) - does anybody have any experience with this sort of system?

not with that specific application but a friend of mine installed a chip on his 2.0 HDi engine and needed the new chip to optimize injection maps after it was installed. But instead of changing the chip, reprogramming the ECU is also an option.

This IC questions came after he installed a chip on his car and the engine started to overheat. he was told to place an IC to solve overheating problems... funny thing is that the guys from SAC also mentions reduced engine temperatures ...due to reduced detonation. But detonation is not the cause for engine overheating (maybe hotspots, but not global engine temperature, right? I think engine temperature (thermal load) is defined by the balance you get between the heat generated by the fuel combustion plus sensible heat of the intake air and that removed by the cooling system, oil circulation and exhaust...so now, i'm a little more confused than i was before :-(!!!

regards
Spereira

 

[aorangi]

"aorangi, the thermal load changes if you inject more fuel...right? and I have a feeling it will increase more than the sensible heat you've manage to remove by cooling the air down."

It depends how much more fuel you inject...

Cheers
Aorangi

 

[patprimmer]

Basically burnt fuel makes a lot of heat, but intercoolers only remove a little.

Also, most intercoolers are ahead of the radiator, so the heat removed from the compressed air in the inlet tract is passed through the radiator anyway, thereby haveing no benifit in reducing coolant temperature, plus additional heat from burnt fuel, equals increased coolant temp in my books.

If it overheats, like everyone else is saying, fix the cooling system, or upgrade it to handle the power you are makeing.



Regards
pat