Edelbrock 3670 User Manual - page 34

34

Figure 12

To mount the ECM or PCM inside the vehicle, a hole will have to be made in the firewall

for the harness and connectors to pass through. A firewall bulkhead grommet and cover

plate is included to seal the hole and support the harness where it passes through the

firewall, or you can make your own.

1. To run the harness into the passenger compartment, select the appropriate

location for the harness to pass through for your vehicle – making sure you have

access from the inside of the vehicle and that no components are in the way or can

be damaged during the process.

2. Use the grommet and cover plate assembly as a template. Mark the outline on the

firewall. - Using a hole saw, nibbler, or chassis punch, create a 2” x 2-3/8”

rectangular hole in the firewall – being sure to center the hole in the template

outline. De-burr all edges when finished.

3. Carefully work the harness through the firewall, passing the 32 pin (PCM only)

connector through first, followed by the other connectors. The ECU connector

covers may need to be temporarily removed in some cases to get them through

easily. - Install the firewall plate with the screws provided by slicing the O-ring and

wrapping it around the main harness bundle. Slide each side over the grommet

and harness until the mounting holes line up as in figure 8. Fasten to the firewall.

Use of a silicone sealant between the plate and the firewall is optional.  See Figure

13.