Here are the functions for the wires of the grey connector. (minimum connections to get you started)
1. The red wire is responsible to switch the system on.
2. The green wire picks up the fuel cutty cycle signal.
3. The blue wire is only required if you want to trigger the system by boost.
Here the addition wires of the grey connector if you evolves from the basic.
4. Orange wire: map switch/failsafe signal to your ECU (if applicable)
5. Yellow wire: addition 0-5V input to alter the flow by +/-15%
6. White, brown and black. Relay output for failsafe.
If you want additional information, please go to the
www.aquamist-direct.com to download the HFD3 user manual. Click on the 806-063 (HFS3-v3)
There is a guide line within the link or the user Manaus recommending the correct jet/jets to use.
Approximately 1-1.5cc/min per BHP. (M50/W50)
BTW, the last inside back page tells your the function of all the connectors.