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Efan questions for the 8.1L

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Old 04-18-2009, 07:56 PM
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Also, with the two pin setup........do the fans auto turn on high when the A/C is turned on? Do the "pressure enable" switches in the PCM work or is high speed only enabled by temperature?
Old 04-18-2009, 09:33 PM
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Originally Posted by Whippled 496
Also, with the two pin setup........do the fans auto turn on high when the A/C is turned on? Do the "pressure enable" switches in the PCM work or is high speed only enabled by temperature?
That's a nice setup, I may have to go that route some day. Looks like your fans for ac are only controlled by ac pressures (which I like), but I don't understand why fan1 and fan2 have different turn on pressures, unless they run at different speeds or something?. I also like that there is a fan turn off speed (don't need my fan running when I'm cruising down the highway at 80mph lol). I don't understand what the "Fan #1 Turn on by AC Temp = 224" is all about though
Old 04-19-2009, 02:02 AM
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What do the numbers mean in the A/C pressure tables? Are they some kind of metric pressure?
Old 04-19-2009, 10:10 AM
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Originally Posted by budhayes3
That's a nice setup, I may have to go that route some day. Looks like your fans for ac are only controlled by ac pressures (which I like), but I don't understand why fan1 and fan2 have different turn on pressures, unless they run at different speeds or something?. I also like that there is a fan turn off speed (don't need my fan running when I'm cruising down the highway at 80mph lol). I don't understand what the "Fan #1 Turn on by AC Temp = 224" is all about though

I am not an A/C guy but i assume that as the temps rise across the condenser, the pressure in the system rises as well? As far as the "fan #1 turn on by A/C" is concerned, it must be a fail safe i guess because the other switches would be satisfied way before that comes into play.

Originally Posted by MikeGyver
What do the numbers mean in the A/C pressure tables? Are they some kind of metric pressure?
Yes they are kPa values.
Old 04-19-2009, 09:19 PM
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Originally Posted by Whippled 496
I am not an A/C guy but i assume that as the temps rise across the condenser, the pressure in the system rises as well? As far as the "fan #1 turn on by A/C" is concerned, it must be a fail safe i guess because the other switches would be satisfied way before that comes into play.
OK, the fail safe makes sense...I also wasn't aware that the PCM monitored a/c temp, I thought it only monitored pressure. Just some quick a/c operation info...As the refrigerant is compressed, it turns from a liquid to a gas and gets hot, then as it travels the the condenser it cools, (the condenser radiates heat), and the refrigerant leaves the condenser as a high pressure liquid. It's very important that the condenser always has good airflow across it for the a/c system to operate properly
Old 12-18-2009, 08:43 AM
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I am running 6.0 radiator with them fans in my 8.1 1/2 ton swap and they work fine. 180 degree thermo stat and it stays there. Any more pics of the whipple on the 8.1?
Old 01-16-2010, 08:34 PM
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you can also adjust the idle air settings to add some air when the fans kick on to get rid of the loss in rpm.
Old 01-19-2010, 05:02 PM
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Any effects performance wise??? Like better MPG's or seat of the pants feel

doubt it though with a wippled 496
Old 07-18-2010, 10:49 AM
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Sorry, have not checked this thread in a while so I know the questions are old.....sorry....

It got rid of the terrible rushing air sound that you get when the fans kick in. Since I have picked up the other 8.1L (daily driver truck) there is a pretty big difference between the two in the way it feels when you take off from a light with the mechanical fan engaged. I did not notice much (if any) of an hp/tq gain....but now that I have the other truck to compare it too, I would say there is definately some difference....just not sure how much.

ED:

I have thousands of pictures.....anything in particular?
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