From 1988 to 1993 fuel pumps were 88 liters/hr., and the 1994 to 2004 pumps were 110 liters/hr. The
Fuel filler neck is also a donor part required for an FFR kit.. In 1999, the tank filler hole and the filler
neck changed to 1" from 2". The pump also changed so that it is controlled by a separate module, a
pulse width modular (PWM), in the trunk location that pulses power using to the fuel pump to control
pressure instead of using a mechanical regulator. The top of the tank was changed so putting an older
pump or gauge sender in the tank is not possible.
Fuel lines, fuel filter and bracket
The fuel filter and bracket is the same from 1986 - 2004. All of the front and rear flexible fuel lines
from the 1986-2004 Mustangs are required donor parts for all FFR EFI kits where the donor fuel rails,
and tank are used.
Emergency brake handle
Emergency brake handles with the attached "T"-junction equalizer bar from 1984 to 2004 all work with
FFR kits.
Rear quad shocks
Quad shocks are attached between the axle and the chassis of solid axle Mustangs from 1983.5 to 2004
to prevent wheel hop. This is a required donor part for all 4-link solid axle FFR kits, and they are also
used for independent rear suspension FFR kits. There is a mounting bracket for the quad shock to
mount to the Mustang chassis which is also used for solid axle FFR kits. The IRS kits do not use the
mounting bracket.
Spindles
1979 to 1993 Mustang spindles used a rotor with built in bearing carrier hubs. 1994 to 2004 Mustangs
used a hub that was separate from the rotor, and is often considered part of the spindle. In 1996 the
mount on the spindle for the tie rod end was positioned slightly different than the 94 and 95's. Factory
Five kits come with a bracket to attach the spindle to the kits upper control arm. In 1999 the lower ball
joints switched over to metric. 1983.5 to 1986 spindles are similar to the 1987 to 1993 spindle except
they are thicker and are designed for a smaller 10" rotor. To use them, one of the shims tack welded
into the standard IFS bracket needs to be removed.
Rear 4 link control arms
Upper control and lower control arms stay the same from 1979 to 1998, and then from 1999 to 2004 the
diameter of the mounting bolts changed to a larger metric size.
Front lower control arms
Front lower control arms from 1979 to 1993 all have the same dimensions and will work with any FFR
kit by following the simple modification shown below. In 1994 the control arms had a similar design,
546
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