I'm really wanting to setup the 2 step launch control on MSnS to help me off the line.

How the other DSM guys do it is with VSS input. Say 3600 rpm regulated till 10 mph or so.

I haven't extensively researched this on the MS forums yet, but was seeing if anyone had any input on the matter.

Joel Baldridge, ASE Certified Master Technician, Audi Certified Expert Technician

You'd have to make a circuit to interpret the VSS signal and switch the ground to the MS input on/off. Using SX/B, the program logic should be pretty straightforward...


Switch PIN OUTPUT
VSS PIN INPUT

Speed VAR Byte
Trigger VAR Byte

SpeedMult CON ? ' VSS Scaling Factor
TriggerCon CON 10 ' Whatever speed you choose...

Start:
Trigger = SpeedMult * TriggerCon

Main:
PULSIN VSS,0,Speed
IF Speed > Trigger THEN Switch = HIGH
ELSE Switch = LOW ENDIF

GOTO Main


Then just build a little circuit with a VREG/caps, output transistor, and a few resistors for protection. Voilà.

The rest of the settings (RPM setpoint, etc.) are controlled by MS.




-http://www.symtechlabs.com/-

Just curious paul, because I'm getting ready to attempt to use this 2step.

When you added the launch control feature to the box you made, those were the steps you did right?

Now besides turning the launch control on in megatune, and typing in the set rpm points, what exactly do I have to wire up outside of the box, and input on megatune?

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~Randy
99 GS(w/turbo)
285whp/300ft-lbs

Myspace:
http://www.myspace.com/420aturbo

Uhh... I included a wiring schematic for the launch control with your unit. I don't have a copy on hand, but I believe it's a switched ground. All you have to do is connect the right wire from the wiring harness to a switch, and connect the other end of the switch to chassis ground.

Launch control is thus controlled by the switch (not by vehicle speed), but you can specify RPM setpoints in Megatune.

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-Paul

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