Adjustable Fan Relay?
 

Ok, for some reason, my car has been overheating lately. Now technically, it's not overheating as the OEM gauge doesn't even move, but with the AC on and on the highway, I'm still seeing 230F or so - which is as hot as I let it go before I shut the AC off.

I installed a Koyo 55mm and plan on really sealing the 1" gaps. I have a 190 (or was that 195F) T-stat, new rad cap, and new coolant. I did all of this less than 1000 miles ago.

The sealing of the radiator should help with the highway temps, but now I need to do something about temps on signal to signal surface street driving.

Anyone know how I can wire an adjustable fan relay? There is a retailer selling one, but they need to know the voltage at several temps. I have the resistance curve. Couldn't that be used to make something?

TIA

there's a ton of standalone cooling fan controllers on the market
this one is a little expensive, but is super simple
http://performanceunlimited.com/cobr...ontroller.html

I would do something along the lines of running it through a SPDT relay to the A/C fan. Would give you a dual stage fan system, with one fan controlled by the ecu at stock settings, but the second fan completely user controllable.

Holy crap! Now THAT'S what I'm talking about!

Le me reiterate that I'm an electronic idiot. I can follow directions only if it's color coded so unless someone can point me to cheaper kit, I'll probably buy that.

BTW, I'll probably also end up buying 2/3 Cobra's SPAL and shroud kit as even with the adjustable relay, I don't think the OEM fans can handle Phoenix heat.

Thanks Ben.

I already got an e-mail back from them.

Many are running on this little device for Water/Oil Temp reading, also the added Fan controller fucntion

http://pivotjp.com/product/flame-controller-e.html

http://pivotjp.com/product/controller/img/stc.jpg

http://cgi.ebay.com/ebaymotors/Geniu...QQcmdZViewItem

There are cheaper Taiwanese copies avalible also!

Yeah, that's all that is to it. I see 3 wires, red, black, blue
Let's ass-u-me
Red: System +12V
Black: System Ground
Blue: Fan Trigger Output

The only thing you need to know if the fan trigger wire switches ground OR if it switches +12V. Either way, you run it to a relay (to the relay coil), and when the coil circuit is completed, the relay's solenoid closes and closes the circuit to the cooling fan.

You could hijack the oem cooling fan relay, or add your own. With my dual stage fan mod, I added a SPDT relay to the a/c side fan. That way the fan still comes on with the A/C, but it also will come on at 207F even if the A/C is off. The only difference between my setup and this one is I'm using a thermoswitch with a non adjustable set point to close the circuit, and you would have the adjustable fan controller. The thermoswitch is a perk of having a 1.6.

I'm sure it comes with printed instructions ;)

I'm hoping for good printed instructions. :)

I may put one of those in the glovebox of the RX7, neat little tool.

I'm wondering if the oil temp probe/sender is included. I can't find much info on this piece.

Frank

The kit shoudl include one sensor only, additinal sensor could be purchased! But beware not all sensor are compataible! Its an resistor style, so that it depends on the ohms.

The Taiwanese copy which I am using now cost about USD$90 and additional sensor may be around $12-13 bucks more!

PS: I am not sure if those unit display Degrees Fahrenheit (F)

HKS has it also!

http://www.hksusa.com/images_products/S_2308.jpg

The HK$ is $200 on ebay.

Mimime, are you displaying both oil and water temps, or just water?

Frank

Frank, I am just using to display water for the time being! But will attach another probe when I install my oil cooler soon.

The display can cycle both values or just display one with one push of a button.

If you guys couldn't find any other source to get the unit, I could arrange something for you guys.

Chuck, check out this neat little controller Rob found
https://www.miataturbo.net/general-miata-chat-9/wiring-high-load-fan-8400/

It would work perfectly as a controller for your A/C side fan.

Might check out
http://www.dccontrol.com
I am using one on my Lightning and it's much better than some of the others that I have tried.

Thanks.

I just ordered the SPAL controller plus the extra wiring for an additional fan.

let us know how it works out! :bigtu:

My plans are to replace the T-stat from a 195F to a Stant 180F, install the fan controller, and close all of the gaps between the rad, AC condensor and the front nose area.

Then we'll see just how hot/cool it runs.