I got a Ground Control coilover kit from Jason @ Paragon Products. A definite must-buy from a company with great techincal expertise and exceptional customer-service. In today's fluid economy with competitive pricing, getting the best products at the lowest prices are commonplace. But service, that's worth paying for and I have no qualms about recommending Paragon Products!
Why 2.5" front coilovers?
There are numerous reasons
to upgrade to a 2.5" front coilover suspension. These include:
- easy ride-height adjustability
(crucial for conner-balancing if you race)
- quick and inexpensive spring-rate changes (from an infinite
supply of 2.5" springs)
- wider selection of inexpensive strut inserts (I used '84
944NA rebuildable struts in my '86 951)
- allows use of WIDER wheels and WIDER tires
- see Wheels-ClearanceBeforeAfter.jpg
and Wheels-FrontClearances.pdf
Remove stock struts &
springs
Before
jacking up the car and removing the stock struts, loosen the big
nut on top of the strut piston-rod first. The weight of the car
helps keep the piston steady. You can use an impact wrench. Or
if the piston spins, depending upon your strut-insert type, you
can use either an allen-key or small adjustable wrench to hold
the piston-rod steady as you reach in with needle-nose vise-grips
to loosen the nut. If that doesn't work, or you forgot to loosen
the nut before taking the strut off the car, you can grip the
strut-piston with some channel-lock pliers clamped in a vise.
Preparing the Coilover kit
Make sure you have
all the components listed before you start. Nothing worse than
having your car all apart and finding you need to run down to
the hardware store. In addition to the '82-85 rebuildable strut
housings, strut inserts, and coilover kit, I also got some 2"
PVC tubing to shim the coilover collars and some 2mm thick angle
reinforcements from Home Depot to shim the spindle-clamp.
Cut off Spring Perches
The
first step is to cut off most of the stock spring perch. Cut it
off in a circle around the strut, leaving a 5mm wide ledge protruding
all around to support the new adjustable spring collars. To be
safe, make sure you measure the diameter of the strut housing
and spring collars (there are different sizes out there).
Install New Adustable Collars
The adjustable collars
are several millimeters too large to fit snuggly on the strut
body; even with the supplied O-ring padding. I've heard other
cars with the Ground Control kit and they make clunking sounds
over bumps when forces from the spring compressing causes the
collars to move around on the strut. I decided to shim the entire
length of the collar against the strut and epoxied the whole thing
together to make one rigid part using this procedure:

Make Spindle-Clamp Shim
The width of the spindle
where the strut clamps is 18mm on the 951 and 20mm on the 944NA
cars. So we'll have to make a 2mm shim to fit. Take one side of
the 2mm thick angle-irons you picked up earlier and lay it inside
the 951 strut's spindle-clamp (don't get this mixed up
with the 944NA strut). Trace the outline of the clamp on the plate
as well as the contours of the bolt holes. Cut out the shim with
any combination of jig-saw, hacksaws, drills and die-grinders
you have. Once finished, put the shim inside the 951 strut and
put the bolts through it to make sure everything lines up. Slide
the shim back and forth to make sure it fits under both sides
of the strut-clamp flush with the inside surface. Rotate the upper
camber-adjuster bolt through 360-degrees to make sure there's
no binding.
Elongate Upper Hole on 944NA
Strut
Take the 2mm spindle shim
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