56 pin timing retard option?

[540gts]

I was told you could ground #56 pin and it would pull timing? Anyone heard of it? And does HPT support it?

Not sure how much it pulls though? Getting ready for nos.
Thanks guys

[Super73]

Funny I find this. I have a friend that is installing a N20 kit for one of his customers. This customer told him to wire in a relay to ground Red 56 so he can pull timing. I have been googling and looking at links and believe EFI Live allows you to use some form of function with Red 56 to pull timing.

That being said, the only way I know of doing this with HPtuners is to use a relay with resistor wired in to either the IAT or Coolant sensor and adjust the base timing there.

But maybe there is something newer that I don't know.

[Nastruck]

On a 2004 Silverado Terminal 56 shows to only be in Connector 1. Circuit 1579 White wire. Fuel temp/Compisition signal for L59 flex fuel RPO code vehicles. On GM site it does say it will change timing due to thinking its on e85 but not sure you can just ground that circuit and to what extent the timing is changed. I didn't really look much into it

GM Service Information. Short version.

The fuel composition sensor (FCS), or flex fuel sensor (service parts term), measures the ethanol-gasoline ratio of the fuel being used in a flexible fuel vehicle. Flexible fuel vehicles can be operated with a blend of ethanol and gasoline, up to 85 percent ethanol. In order to adjust the ignition timing and the fuel quantity to be injected, the engine management system requires information about the percentage of ethanol in the fuel.

The FCS uses a microprocessor inside the sensor to measure the ethanol percentage and fuel temp, and change an output signal accordingly. The electrical characteristic of the FCS signal is a square-wave digital signal. The signal is both variable frequency and variable pulse width. The frequency of the signal indicates the ethanol percentage, and the pulse width indicates the fuel temperature. The PCM provides an internal pull-up to five volts on the signal circuit, and the FCS pulls the 5 volts to ground in pulses. The output frequency is linear to the percentage of ethanol content in the fuel. The normal range of operating frequency is between 50 and 150 Hertz, with 50 Hertz representing 0 percent ethanol, and 150 Hertz representing 100 percent ethanol. The normal pulse width range of the digital pulses is between 1 and 5 milliseconds, with 1 millisecond representing −40°C (−40°F), and 5 milliseconds representing 125°C (257°F).

[PICNIC_GEORGE]

In efilive cos5 you can ground pin 56 and have a nitrous tune. Pull timing with {A0016} N2O monitor timing table. You can pull up to 20* at any RPM(in 400 rpm increments). There are a few other things you can do as well.

[LSxpwrdZ]

If it's a cable throttle OS you are using then you can just use traction control which is Red connector Pin 53. Grounding it will pull the amount of timing in the traction control retard tables. There are a few other things that need to be setup as well like the maximum runtime... it needs to be maxed out to 410 seconds. This will keep the PCM from tripping a code and disabling traction spark retard.

[540gts]

If it's a cable throttle OS you are using then you can just use traction control which is Red connector Pin 53. Grounding it will pull the amount of timing in the traction control retard tables. There are a few other things that need to be setup as well like the maximum runtime... it needs to be maxed out to 410 seconds. This will keep the PCM from tripping a code and disabling traction spark retard.

Wow does that really mean I wouldn't need a timing box? That would be great, cleaner install. I am going to run a Maximizer 4 or a Micro Storm 2 stage, not sure which. Anyone know of any other threads r articles that might help?

[MikeOD]

If it's a cable throttle OS you are using then you can just use traction control which is Red connector Pin 53. Grounding it will pull the amount of timing in the traction control retard tables. There are a few other things that need to be setup as well like the maximum runtime... it needs to be maxed out to 410 seconds. This will keep the PCM from tripping a code and disabling traction spark retard.

Have you ever found a way to do this with an ETC OS? Say in a 2003-2006 Silverado?

[charcoal03silvy]

You http://www.hptuners.com/forum/showth...ng-for-nitrous

[MikeOD]

You http://www.hptuners.com/forum/showth...ng-for-nitrous

Yeah, I want to do it without the IAT trick if I can...though that's not the end of the world.

[540gts]

Yeah, I want to do it without the IAT trick if I can...though that's not the end of the world.

Me to, Mike

I like the idea of using the engine temp file with resisters and get a visual cue from temp gauge it is working. Working on it now, but not sure how many ohm's to start with. Any one know any pro's or cons with this set up?

[LSxpwrdZ]

I've not been able to get the traction control spark to work on ETC vehicles. I'm sure there is a way to swap a segment or something from a normal cable TB OS and then possibly re-enable ETC in the cable OS to see if it would retain the spark retard pin. I'm sure there is a switch in the software somewhere that we don't have access to that would enable it. I'm assuming the reason the ETC vehicles don't utilize this manual spark retard pin is because the traction control systems work with the electronic throttle systems via serial communication.