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I never paid much attention in shop class but here's my question.
I want to wire two radiator fans to run at two speeds simultaneously. While the car is running I want the fans to run at half speed to draw some air over my two intercoolers. When I get into boost I want the fans to run at full speed. Now the fans are 12v 6" fans from a Yamaha R1 cycle. There's no markings on the fans showing the amps. I can't find any special switches to run the setup and ideally I'd like to have the low speed setup to come on with a thermal switch at 80-90 degrees but that would require drilling and tapping the IC and that's no good.
What I thought might work is to run two relays: for full speed, a relay connected to the accessory interrupted by a hobbs switch so that it only gets energized when in boost and both fans in parallel; for half speed, a relay connected to the accessory power and both fans in series effectively giving each 6v. My concern is the amps would be double and overload/heat would be an issue.
I would really appreciate help from someone who understand electrical circuits.
How many wires are coming out of the fan motor? If there are at least three then you have a two speed fan. If there are only 2 wires coming out of the fan motor then it is a single speed.
The wiring that you were thinking of would be quite complex and not work properly for the low speed setting and possibly damage the electrical system.
With the info on the fans I can draw a circuit that will work. PM me if interested.
How many wires are coming out of the fan motor? If there are at least three then you have a two speed fan. If there are only 2 wires coming out of the fan motor then it is a single speed.
The wiring that you were thinking of would be quite complex and not work properly for the low speed setting and possibly damage the electrical system.
With the info on the fans I can draw a circuit that will work. PM me if interested.
Gary
2 wires. I'm playing around with a diagram now and I'm up to 4 relays.
I should have said: The setup has twin intercoolers, so both fans need to run simultaneously. 1 fan per IC
All-Righty then.
How about 2 fans wired in parallel thru ONE relay controlled by the Hobbs switch (whatever that is ) that's used to switch in/out a 12V - 6V ballast resistor? You could use a rheostat to determine the resistance required to get the results you want.
All-Righty then.
How about 2 fans wired in parallel thru ONE relay controlled by the Hobbs switch (whatever that is ) that's used to switch in/out a 12V - 6V ballast resistor? You could use a rheostat to determine the resistance required to get the results you want.
Sounds simple enough. what is a ballast resistor and where can I find one? The Hobbs switch is a switch which opens and closes a circuit based on boost (positive pressure). It would be off in vac and on in boost or visa vera depending on how you wire it. A simple switch.
For anyone curious about what I'm doing, here's what I've started today. After carefully measuring the intercooler and making accomodations for bends and seating edges, I cut out the 0.9" Lexan and heated it to 375 F and pressed it into a wooden mold. As flexible as it was in the oven it was resistant to forming. But it worked well enough to get me the 1/2" lift I needed on top of the 3/8" weather stripping, the total distance from fan to IC is 3/4". The only way to mount it without damaging the IC is with 4 long zip ties at the corners. Its not complete yet but here's some pics. It's a fun project if anyone has similar intercoolers on their car. Otherwise they are not very efficient. These fans will constantly draw cool air over them and bump up to full speed when I'm in boost. I plan to use a 3 position mini switch to turn them from off, to low(const)/high(in boost) and full time high speed. I chose lexan over ABS because it is just as strong, flexible and allows me to see what's going on.
As you can see, it's very tight quarters and needs a small, flat fan to fit. The Yamaha R1 fans worked perfectly.
The install is complete and I wonder if running them entirely in low speed (in series) would be sufficient. There is a strong flow of air at low speed and so much more in high speed. This is definately going to help. I couldn't find a way to activate the fans with a temp sensor so they will operate off a boost switch. low speed off boost and high speed in boost. Total project was less than $80. You've seen the fans already and there's not much to see once the bumper is back in place except for the switch and relay placement: