MSD 2957 Atomic LS Master Early Truck Kit (GEN III 1999-2007) Installation - Manual (Page 13)

INSTALLATION INSTRUCTIONS 13
M S D
• W W W . A T O M I C E F I . C O M • ( 9 1 5 ) 8 5 5 - 7 1 2 3 • F A X ( 9 1 5 ) 8 5 7 - 3 3 4 4
WIDE BAND OXYGEN SENSOR INSTALLATION
The MSD Atomic EFI system requires a single Wide
Band Oxygen Sensor (WBO2) for operation. MSD
suggests that the bung for this sensor be installed
prior to starting any other part of the conversion
process. By having the WBO2 in place first, there is a
reduced chance of the vehicle being immobilized for
an extended time. The bung for the WBO2 provided
by MSD has a plug included so that the vehicle can
be driven between the time of exhaust modification
and installing the rest of the Atomic system, if needed.
The WBO2 can be installed in either exhaust bank.
The sensor connects to the Power Module, so install
the sensor on the bank closest to where you plan to
mount the Module. The bung should be installed by a qualified exhaust technician and pressure tested.
Proper installation of the oxygen sensor is critical to the performance of the Atomic EFI. Improper
installation could lead to engine damage.
1. Locate the ideal spot to install the WBO2.
a. This location should be 2-4 inches after the exhaust collector. The sensor must be more than
18 inches forward of the exhaust tip. For applications where short or open headers are used,
install the WBO2 in the primary tube of the rear cylinder at least 8 inches away from the exhaust
port. The Atomic will not work on “Zoomie” style headers.
b. The WBO2 sensor should be at least 10˚ above horizontal to allow condensation runoff.
Without this angle the sensor is significantly more likely to sustain water damage (Figure 27).
c. Never place a WBO2 on the outside of a bend.
d. The WBO2 must be mounted in the exhaust prior to any catalytic converter, if applicable.
2. Drill a 7/8” hole in the exhaust where the WBO2 will go.
3. Weld in the supplied bung. Ensure the weld goes completely around the bung and is air tight.
4. Insert supplied plug in bung. Never run the vehicle with a WBO2 installed but not plugged in to
the harness and powered up; it will damage the sensor.
5. When completing the Atomic EFI installation, remove the plug and insert the WBO2 for use. MSD
suggests using a small amount of anti-seize on the threads.
Note: The Atomic EFI is extremely sensitive to air leaks in the exhaust system. Any air leak between
the engine and the WBO2 will cause the Atomic to have false readings, which can lead to poor
engine performance, misfires, and an inability to properly auto-tune. Extended running of the
Atomic EFI with an exhaust leak can result in detonation and severe engine damage. Improper
installation of the oxygen sensor, and any damage that may result from such an installation,
is not covered by the manufacturer’s warranty.
Figure 27 WBO2 Sensor Location.
POSITION
AT LEAST
10°
02 SENSOR
EXHAUST
COLLECTOR