Vortech 1994-1995 7.4L TBI Truck/SUV User Manual
Page 14
P/N:
4GC020-010
©2001 Vortech Engineering, LLC
All Rights Reserved, Intl. Copr. Secured
15SEP01 V1.1
(88-95 GM Lt Trk(4GC))
D. Mount the additional fuel pump to the inner side
of the frame rail beneath the driver's side floor.
Use the shorter hose provided to help locate the
pump the correct distance from the filter. This
hose has an adapter fitting on the filter end.
Secure the pump to the frame and hose with the
clamp and fastener provided. (See
Fig. 5-a.)
E. Mark and drill a 3/16" hole in the frame near the
fuel pump to mount relay and wiring harness.
Mount relay with supplied #10 hardware.
F. From relay terminal #85, tap the yellow wire into
the solid gray wire in the harness running along
the driver's side frame member. Use the sup-
plied scotchlock.
G. Connect the short red wire from relay terminal
#87 to the (+) terminal on the fuel pump.
H. Connect the longer black wire from the (-) termi-
nal at the fuel pump to a clean ground.
I. Connect the short black wire from relay terminal
#86 to a clean ground (relay screw mount works
well).
J. Connect the long red wire from relay terminal
#30 to a (+) battery lug located in the engine
compartment.
K. Plumb the pump to the supplementary injectors
as per the schematic on page 5. Much of this
assembly has been done by Vortech.
L. Plumb the new pressure regulator and outlet,
routing the regulator to the throttle body inlet
using the adapter fitting and O-ring.
M. Route the Vortech SFIC wiring harness and
vacuum line through the firewall. Mount the
SFIC unit inside the vehicle beneath the steer-
ing column using the Velcro
®
strips provided.
N. Connect the wires for the Vortech SFIC. Attach
the black wire to ground. Connect the red to the
"4WD" fuse location in the stock fuse block (this
location is also found on 2WD trucks) with the
special adapter provided (on 1995 models, the
fuse box containing the "4WD" fuse is located
inside the vehicle on the left hand side of the
dashboard). Connect the brown wire to the
negative side of the ignition coil tach pickup
(loose male connection located on coil har-
ness).
5. SUPPLEMENTARY FUEL INJECTION COMPUTER AND RELATED SYSTEM - Cont'd.
NOTE: Make sure all small holes are aligned and
not plugged with gasket sealer when in-
stalled.
4