Read vehicle speed from vss or ECM

[GNandTTA]

Is there any way to read from the vss sensor or the ECM to tell when the car is moving at approx. 10 mph. Want a low amerage output to drive a transistor, etc. I built side baffles for the TTA that work in conjunction with the factory ones and force alot more air through the intercooler and radiator. But with them on the car right now, going up a curb or parking are trashing them very fast. I want to motorize them so when under 10 mph they are retracted and once you get moving they lower down into place. I know I could probably tap off of the 2nd gear solenoid output but wondered if there is a better way.

 

[QuickWrench]

3 ways to do this:

1. Boost Sensing
You're not going to care about additional airflow through the IC unless you're under boost, anyway. A simple Hobbs switch works great.

2. 2/3/4 gear switch. No brainer here.

3. Cruise Control
Find the pinout for the CC. One of the pins carries the VSS signal, and it's already under the hood.