View Full Version : IC Fan. WoW!!! and some questions. . .

10-03-2009, 01:22 PM
IC fan's have been a long debated topic on this forum. I know this, as I have read like 500 of them. First, just let me say, OMG. IT really did make a seat of the pants gain. Before the fan I swear I could feel the computer pulling the timing, especially at high boost. After installing the fan, it seems to have more torque throught the power band as well as on the fly. If anyone is concidring such an upgrade, I highly reccomend it. worth every penny. The install wasn't too bad, just need little hands. It DOES make a difference.

Now some questions:

1. I have read on many posts that the gains are only to be made when it's hot outside, and in fact many users, disconnect the fan during winter. This seems unlogical to me. From my airplane knowledge, I have witnessed that EGT's remain unchanged throughout an altitiude change (cooling temps), and the only thing that changes it is a change to the fuel air mixture, or to the throttle setting itself. So if a cooler running engine is what your after, then how could this be effective for that? (Some members have stated this.)

2. The output from the SC is heated due to compresional heating, correct? So wouldn't running a fan when the air it draws thru the IC is much colder would't there be a coresponding decrease in the ACT? And thereby increasing engine performance and efficency even further in cold weather, as opposed to in the summer? No doubt there would be a benefit in the summer, but that benifit would be amplified in the winter, the same as adding ice or spraying liquid on the IC itself? A difference of say 30 degrees of inlet air temp is insignificant to the 100's of degrees increase from the compression of the air in the SC. But coolder air over the IC would be paramount.

I have thought up some other questions, but I can't remember them right now, and this post is long enough. Please let me know if my thinking is correct.



10-03-2009, 01:45 PM
I agree with your logic. Every air compressor I've worked on uses a after-cooler (inter-cooler) all year long (though will say this is more for drying than anything else).

The only time I'd say to turn off the IC fan is at speeds were it cause a greater restriction than it can flow, just like the Rad fan.

10-03-2009, 02:47 PM
just kind of scimmed it but form past experience with turbo'd cars I can say cooler weather for sure ups the performance. here in Iowa we get anywhere from 100*~ to -20*~ in a given year. currently highs are only in the 50's (may be even lower) as apposed to two weeks ago when they where in the 80's. boosted cars around here LOVE to run at night for the simple reason that the cold air nets substantial gains (being free I would call any gain a pretty "substantial" one)

10-03-2009, 11:46 PM
agreed. and the restriction is a non event as the poor placement of the stock IC net almost negligible airflow even at high speed. I once seen a chart that someone had constructed of the speed in mph thru the IC but have been unable to refind it. So this paticular fan is good all the time. The bottom line of my post was simply to say. . . Hell yes. The IC fan is a worthwhile investment in a better performing car.