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Discussion Starter #1
question for people with intercooler fan, how do you guys control when to turn on and off the fan? Is it constant on, or with temp sensor or speed sensor...?
 

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You can install an on/off switch to the temp sensor. When the switch is "on" (closed circuit) the sensor will work and control the fan by the temps in the engine bay. If you turn the switch to the "off" position it is no different than disconnecting the plug on the sensor itself and then the fan will run all the time.

Gives you a little bit of control, and even while you have it off it will still come on when its warm enough in the engine bay.

I find it quite annoying to have the fan come on as soon as your key is turned, like it will with the sensor unplugged.
 

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You should just wire it so it's on all the time. The sidemount intercoolers need all the help they can get, and the 7.5" fan is not going to significantly impact engine warmup time. If you have a switch on it, it would be easy to forget to turn on the fan, and you could get heat soak and detonate. If you use the stock fan control circuit, the fan only turns on when the engine bay exceeds 140F, which I can assure you, almost never happens.

Best regards,

Ken
 

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Discussion Starter #6
Thanks for the advise. Would it be possibe to wire it, so it's control by the speed, I was thinking to have the fan on between idel and 30mph. automatically off after 30mph.
 

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Discussion Starter #9
well I'm running a 10" fan, I might just let it run constant, I figure that it'll last at least 2 years. Fans are only $60 , might as well run cooler all the time.
 

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Slightly OT, but does anyone know where to get the keyed male electrical connectors that will mate with the spal connector? Or similar keyed connectors?
 

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I have a switch installed for my sensor, not the fans.
So my options are:
1. Fans operated by temp sensor
2. Fans constantly on

During normal driving, I let the temp sensor do it's thing.
While at race events I flip the switch so the fans are constantly on helping control heat soaking of the IC.

Before I pull up to the line, I switch back to the sensor and 9 tiems out of 10 the fans will go off (less draw on the alternator).

I have 2 7.5" Spal fans on my GReddy IC. One push and one pull for maximum benefit.
I bought the fans through ATS Racing ;)
 

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Hi Larry,
If mounting one fan to the intercooler, I usually cut the connector off, and solder on the stock connector, then plug it back into the stock wiring, unplugging the temp sensor so the fan runs all the time. The SPAL fans are made in Italy, so I don't know how common that connector is going to be here.

Best regards,

Ken
 

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RedTuna, I cut that off and cut the connector off of the OEM IC fan. Then put the OEM fan connector on the Spal fan so it plugs into the stock wiring.

Jeff, that is what I suggested to do, but as others will say the IC will still be able to get heat soaked during normal driving with some hard pulls and if you just have it on all the time it won't happen as easily. It does however beat having a totally seperate power and switch that will allow the fan to NEVER run. At least with putting a switch on the sensor even when it is "off" the fan will still come on as with a stock setup.

I just don't like the fan coming on as soon as I turn the key. I'm not sure anymore but doesn't the fan come on even when the key is at accesories if the connector is disconnected?
 

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JekylandHyde said:
I have a switch installed for my sensor, not the fans.
While at race events I flip the switch so the fans are constantly on helping control heat soaking of the IC.

Before I pull up to the line, I switch back to the sensor and 9 tiems out of 10 the fans will go off (less draw on the alternator).
Of course the fans go off, I'm sure it's less than 140F in the engine bay when you're at the line, unless ambient temperature is very high.

As soon as you turn the fans off, your intercooler starts heat soaking. You will also hit at least 10 degrees higher peak post intercooler charge temp with the fans off:



Best regards,

Ken
 

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I would think that while I am going down the track or racing up a hill there is enough ambient air flow through the engine bay to keep the ambient temps in the engine bay below 140 degrees.

Regardless, I run water injection all the time :)
 

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Thanks, guys. The insulation from my stock fan wiring is cracking so I was hoping someone had found a substitute. Guess I'll just wrap it.
 

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JekylandHyde said:
I would think that while I am going down the track or racing up a hill there is enough ambient air flow through the engine bay to keep the ambient temps in the engine bay below 140 degrees.

Regardless, I run water injection all the time :)

That's true. the goal however, is not to keep engine bay temps down. It's to keep charge temps down. 140F is detonation territory. If you look at my chart, the post-ic peak temperature is almost always 10F colder with the fan on, reducing the chance of detonation.
 
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