H20 – (black, 2-way packard connector), Air – (gray, 2-way packard connector), Coolant_temperature – Precision Turbo and Engine BigStuff3 GEN3 PRO SEFI System Hardware & BigComm Software User Manual
Page 22: Air_temperature
BigStuff3 Pro SEFI System
Version 2.1 – February 2011
19
CAM – [(Gray, 2-way Packard connector with a separate ground wire (3/8” ring terminal)]
For distributor based applications, BigStuff3 recommends using the cam sync input. The cam sync
input is required for all coil-on-plug applications. The GEN3 system will to operate sequentially
without the cam sync hooked up, but the point of injection (the
number of degrees BTDC where the fuel is injected) will vary
every time the engine is started. Individual spark control per
cylinder will also not function without the cam sync hooked up.
The 3/8” ring terminal must be fastened to a secure ground
location, preferably on the engine block near the Cam sensor.
The main wire harness side Packard connector must be connected
to the sensor. The system is supplied with the sensor side mating
connector, terminal and seals, which needs to be configured per the table below.
BS3 2-Way Gray Cam Connector
MSD Synch Pulse
A – Red (+)
A – Green (+)
B – Black (-)
B – Purple (-)
H20 – (Black, 2-way Packard connector)
This connector mates with a GM (only) coolant temperature sensor.
Air – (Gray, 2-way Packard connector)
This connector mates with a GM (only) air temperature sensor.
IAC (Idle/Air Control) – (Black, 4-way Packard connector)
The base main harness IAC connector was designed to work with a GM style IAC motor and valve
assembly with a 2 by 2 connector. If a GM style IAC motor and valve assembly with a 1-by-4 in-line
connector is the factory installed IAC, the 2-by-2-
connector can be removed and replaced with a 4-by-1 in-
line connector per the pin-out table below. The 1-by-4
connector is available from BigStuff3. The
LS1/LS7/Ford Mod Motor systems main harness IAC
connector is a 1x4 GM style IAC motor connector.