Low and high speed fans...
#1
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I am still debating which fan setup I want to go with. They are going to be pushers or maybe a single pusher but my question is do I really need the low speed? How do the stock one works? If I go single I would imagine its has a low current for low speed and the second relay closes for high speed. Is that correct? Thanks guys!
-Alex
-Alex
#2
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The stock setup has three relays. For low speed it connects the two fans in series so that there is ony 6 volts across each. Next it connects only one fan to 12v. For high it connects both fans to 12 volts.
Don't recall seeing any but I would bet that someone makes a dual speed fan. Do you have a Seco Performance store in your area, or you might check Jegs or Summit racing.
Don't recall seeing any but I would bet that someone makes a dual speed fan. Do you have a Seco Performance store in your area, or you might check Jegs or Summit racing.
#3
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The easiest way to understand the fans is to look at them as primary and secondary instead of low speed and high speed. The way the factory wires them on the later model cars is a little complicated.
If you set them up the way the factory did it in 93 and early 94 it's much easier to understand and hook up. The primary fan comes on at one temperature, and if the engine continues to heat up, the secondary fan comes on. It's just two different temperatures programmed into the PCM
If you are going to use one fan only just use the "primary" control wires and forget the secondary. One relay, one fan, and just program the on/off temps based on the thermostat you are using. The fan will then come on at the programmed coolant temp and shut off at the turn off programmed temp.
Nice and easy!
If you set them up the way the factory did it in 93 and early 94 it's much easier to understand and hook up. The primary fan comes on at one temperature, and if the engine continues to heat up, the secondary fan comes on. It's just two different temperatures programmed into the PCM
If you are going to use one fan only just use the "primary" control wires and forget the secondary. One relay, one fan, and just program the on/off temps based on the thermostat you are using. The fan will then come on at the programmed coolant temp and shut off at the turn off programmed temp.
Nice and easy!
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91 Z28 LS2 408CI, LS9 Supercharger, LPE GT7 cam, Yank3000, 3450 raceweight.
Latest numbers: 9.71 ET, 141.42 MPH, 1.40 60' , 610 RWHP Mustang Dyno
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![](https://ls1tech.com/forums/signaturepics/sigpic1124_1.gif)
91 Z28 LS2 408CI, LS9 Supercharger, LPE GT7 cam, Yank3000, 3450 raceweight.
Latest numbers: 9.71 ET, 141.42 MPH, 1.40 60' , 610 RWHP Mustang Dyno
www.speartech.com
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im only running one fan... it comes on at the temp i set in HPtuners, and cuts off at the temp i set... it also cuts off whenever i go faster then 35mph (or whatever i set)
reason im only running one fan is that my car only came with one from the factory... and ive seen this one fan keep much larger and more powerful engines cool... my LS1 never overheats, even sitting in traffic in the heat of summer... so i dont see any reason to change it for now.
reason im only running one fan is that my car only came with one from the factory... and ive seen this one fan keep much larger and more powerful engines cool... my LS1 never overheats, even sitting in traffic in the heat of summer... so i dont see any reason to change it for now.