Highlander

I know that the trac control equipped cars use 4 channel setups and have an additional bcm for the traction control...

My new rear will have support for both 3 channel and 4 channel setups..

This is because i will be using a racelogic traction control unit...

I was wondering another thing about the trac system on the pcm.. if you enable it but still have the 3 channel, will it retard timing according to slip??? although slip will not be ELIMINATED via retard, it could fine tune some traction or help you in controlling slip...

anyone ever used it?

1fastlt1

I wondered the same thing! Although I never tried it.

Ryan94ZA4

When you enable TC in the PCM all you are doing is allowing the timing to retard once the traction control module activates. It is located by where the pedals hook up inside the car. To have true traction control, you have to have the traction control unit itself to do the retarding when slippage is sensed. I just use the TC tables as a nitrous retard. Activate the input wire and it pulls the timing out; kind of a poor man's digital 6....

Ryan

1fastlt1

so i guess one could hook up a switch and do it manually if you were say driving in the snow or rain where you know it's going to spin! Maybe a momentary switch on the shifter or have it activated at full throttle when the switch is on.

Highlander

Ryan!!! Can you please let me know which cable this is ?? and how did you hook up the switch??

Thanks

jhawk

Yeah, break down how exactly you are activating this retard. This is an awesome idea.

jim

Highlander

its a switch from a pin on the PCM i saw it... excellent idea really

Ryan94ZA4

I have used this input wire for multiple uses. Here are a few:

1. Put an actual on off switch on the wire. When the switch is on, you are in low octane mode as it will pull timing out across the board however you set it. When the switch is off, you can run higher octane gas with more timing. I also use the output from the PCM to illuminate and LED or light so you know what mode you are in.

2. Same as 1 but for supercharged or other FI applications, you can flip the switch in case you get some bad gas to eliminate detonation.

3. Use it for nitrous retard. I have it wired so the activation switch for the nitrous and the full throttle switch are both in series. This way, even if the switch is on, the PCM will not retard timing until you are at WOT. I use the system active output from the PCM to operate the nitrous relay. This way, you know when you are spraying, the timing is pulled. If you are like me and like to run stealthy, this works nice as you have no visible timing retard box when you open the hood.

Now, for the wires you use:

You have to add these wires to the PCM most of the time. I have run into a few cars that I suspect the harness may have been replaced and the wires were already there when the car did not have TC.

Pin A23 (red, pin 23) This is the spark retard request wire. This is what tells the PCM that you want the timing pulled.

Pin C27 (clear, pin 11) This is the output wire from the PCM that can activate a relay or an LED or light bulb so you know everything is working.

To test this, I always test it without a power adder. I put a constant retard in across the board and drive then activate a switch. YOu should feel a definite loss of power. Also verify the light illuminates when you push the button. You can drive or just let the car rev a little then activate it to test. Once you have verified it works, hook it up however you plan on using it.

Hope this helps you guys out.

Ryan

jhawk

Awesome, thanks for the info.

jim