What would you like in a E-fan relay controller

[bakerelectronix]

I'm working with DynaTech to designing a new module to be used with the LS1 but would like input from anyone. I currently have an adjustable fan relay controller but I won't work very well with the LS1 (I don't know about the LT1). You can look at www.bakerelectronix.com for the AFRC. The module I have taps onto the stock temperature sensor that the PCM is using and turns on a relay when the selected voltage is reached. It is adjustable from 0v to 4.8 volt. Unfortunatly the LS1 changes its sensitivity at 51C/125F which makes the measured voltage jump back up. My current module would turn the fan on in the low scale (below 51/c125F) then again in the high scale.

what temperature range would you use?

If it you could have two outputs (high speed low speed fans) but only one could be adjusted which would you like?
You may be able to have two modules hooked up to the temperature sensor wire with each with a different setpoints one for the low-speed fans and one for the high-speed fans.

do you know if the LT1 PCM changes its sensitivity like the LS1.

do you have any other ideas.

[farmtruc]

ahhh, too late, I've already developed one that is going on sell tomorrow.

sorry bout that, maybe you can....jk

i'm kind of confused on your question, are you asking what two temps would be nice to have?

if so, that would depend on the tstat,

i'm probably way off on your questions, but just thought i'd start the topic off,

sounds like a great idea, def. keep us updated


allen

[Dynatech]

What Baker forgot to mention is that this module snoops on the LS1, Votec Coolant temp sensor (CTS). No external sending unit is needed for this.

of your module.

[BigKID]

If I understand correctly.. you can only make one fan cuton (high/low) temp adjustable? If that is the case I would have to say high. If you are installing fans on a truck where we originally didnt have fans, it all depends on what size/cfm fans you go with to how low you can set the temps. And like Allen said, it depends on what thermo is in there too. For a generic number I would have to say 170 for the low speed and make the high adj between 170-200 and include the a/c high speed cuton.

[bakerelectronix]

I'm trying to use the same circuit board and 8pin microcontroler that I have used on our other fan controler so I'm limited on inputs and outputs. If lot of people seem to want to adjust both fans then I will have to design a new board and us different microcontroler or I will have to come up with a way to just allow two modules to snoop the stock temperature signal and one would be set lower for the Low-speed fans and one would be set for the High-speed fans, I prefer this options as I think it is more flexible for everyone.
The Holden Service training manual says the LS1 turns the H-fan on above 226F/108C and turns it off below 216F/102C and the L-fan turns on above 208F/98C and turns off below 203F/95C.
So maybe fixinig the Low speed fans to 170F (or the stock 208F?) and being able to adjusting the High speed set point from 170F to 226F would be a good range. That would make the setpoints adjust in 8F steps from 170F, 178F, 186F..226F.
As far as the A/C fan request goes the LS1 seems to use a 0 to 5V presure sensor for deturming when to turn on the low and high-speed fans. I can snoop on this signal and turn on the fans at the proper presure. But, I would need to find the presure sensor output voltages for 2500kPa, 1900kPa, 1500kPa and 1170kPa as these are the setpoints for the Hfan on, Hfan off, Lfan on and Lfan off.

Does anyone have date for pressure vs. voltage for that A/C presure sensor?

Another way is just to use the A/C relay drive signal to not only turn on the A/C clutch but also to turn on the High-speed Fan relay.