Outer Limits 4x4 Board

can anyone tell me the pro's and con's of how to wire up a thermo fan on a water to air IC radiator? I have been thinking of running some kind of thermoswitch in the line between the IC output and where it goes into the radiator. So when the coolant reaches a certain temp it turns the fan on.

what sort of temps should i set the switch to? is it better to just run the fan anytime the ignition is on?

I am fitting the radiator on the headboard of my tube tray, directly behind the drivers side so as to limit how much it affects vision out the back. is it worth making a slimline ram duct between the cab and tray to the side opf the car like the cold air intake on a commodore to funnel air or should i just rely on the thermofan?

I've also got a range of radiator sizes tochoose from. With a 1hz running about 10-12pound, 12x4 inch barrel, what is the optimum size radiator? at what sort of square area does it become overkill?

thanks in advance

MILO

surely someone has some experience with these things?

edit - oops. forgot that it's been a busy weekend for most

i ran my thermo controller on the lowest setting and found that it cut in at about 80deg. but this was on petrol so not sure about diesel. you dont wanna run them all the time as the motors will burn out.

good luck mate.

I'd say just hook up the thermo controller and a temporary thermometer then adjust it according to water and exhaust temps (i.e. check at what point rising water temps have an effect on EGT's). Shouldn't take long to get to a decent setting - i don't suspect fluctuation in water temp wouldn't be too dramatic.

This is what i plan on doing.

thanks guys

If you get on board with the group buys for the EGT gauge you could use that, they have an adjustable switchable output and you can see the temperature.

Cheers

Joel

This is assuming the fan is the only air source so front mount would be different.
The idea of an I/C is to be as cold as possible. So why would you want it to be warmer than it could be??? My I/C fans are switched with the fuel pump for the surge tank so if the motor is running so are the fans.
The same goes for the water pump. I think you want the water pump and the fans running all the time.

If you were going to control them then it would be by air temp not water temp anyway. But you would then want the fan and pump to run for a bit after the air temp was increased so you'll need some sort of timer as well?
Much easier to just let them run and have an overide. (which is what I have done)

There isn't much point running fans while cruizing at 100 kph, most fans cannot displace as much air as high road speed, you will find in most manufacturers tunes with electric fans that they are turned off at high speed as they would slow the air through the radiator/cooler if on. Fit the pyro probe into the air outlet of the cooler and switch away while being able to see the temp too.

Joel

i am currently planing a water 2 air system for the lux and found this switch that i'm thinking of using, set it too stop the thermo at about 40kmp/h where its no longer effective

http://autospeed.com/cms/article.html?&A=1043

or if your really tight you could use the pressure switch for fill cut-off from an old washing machine

I rather like that idea. I think combined with a shroud similar to a cold air intake just poking around the side of the tray, it should be good.