> Front
suspension arms:
The suspension up front is fairly
straight forward, more or less a standard Hyper 7 Pro set-up. The main
changes made is a slight relocation of the upper mounting point for the
hinges on the lower arms, done in order to slightly increase the ground
clearance. I did this by making my own bulkhead of sorts from a chunk or
aluminum. as well as a new front brace to line up with the re-located
hinge. Upper and lower arms, as well as shock tower is stock.
> Front
shocks & mounts:
As with the arms, the shocks and
mounts are pretty much straight off the Hyper 7 Pro. The shock tower is
stock, and the shocks are long (rear) Hyper 7 Pro shocks.
The rear suspension was a
whole new ballgame. I needed something that would work with my Mad Force
rear axle, and something that would take the abuse I had planned for this
truck without disintegrating at the first "blip" of the throttle.
> Upper Link(s):
Due to the overall
oddness of the layout of this rig, I went through a number of different
ideas and brain-farts when it came to the rear suspension (not that all
the brain-farts where limited to this area...). Most of the head aches
revolved around the upper links of the suspension, where due to certain space restrictions
I initially tried a 3-link type suspension,
with a single upper link and a pair of lower suspension arms.
> Version #1:
On the
upper end of the link I needed a set-up which would move up and
down, but not from side to side. For this a milled a chunk of
aluminum into a "T" section, with a 5 mm whole running thru the top
for mounting to the chassis, and threaded for a 5mm screw in the
bottom end for the link itself. The ends of the upper t-section
where bored slightly to seat a bushing on each side to support it
against the chassis walls.The link I made from stainless steel
tubing which I threaded for 5mm screws in each end.
The 3-link version had a lot going for it in terms
of simplicity and "clean" look, however it ultimatly turned out to
more of a hindrance than a help when I found it would conflict with
my rear driveline.
After the problems with driveline clearnaces and
such I decided to go back to the good ole 4-link set-up. I milled a
pair of combined upper/lower link mounts which I fittet to the rear
of the pan chassis where I fitted a pair of upper links which in
turn mounted to the center (pumpkin) of the rear axle diff. (Note:
the 2 piece link mount was later replaced with a 1 piece version.)
Upper Link mount- Version #2
Version 3 is really just a slight refinement to
version 2, where I replaced the 2 piece link mounts with a
single-piece unit, which also provided a mounting for a simple sway
bar.
Upper Link
mount- Version #3
> Lower
Suspension arms:
For the lowers, I milled a pair of
aluminum links that I treaded the M5 threads on the ballends. I then
milled slots for the shocks (yes, for link mounted shocks). The captured
ballend on the axle end is made to mount directly under the rear axle thru
a 5mm hole drilled in the axle housing. Trimmed down it will still give
enough room for the axle (would be a bummer if it didn't, wouldn't it -
LOL) Oh, and I "flipped" the hub carriers so that I would get a nice &
"low profile" mount for the captured ballend (didn't want it to stick too
far out). I finished them up by tapering them a bit towards the ends and
drilled & tapped shock mount holes.
"Rough cut" of the lower arms
Lower arms mounted to Mad
Force axle
Completed lower arms
> Rear Axle
First I should mention that I did
modify the rear Mad Force axle slightly. In order to make it the same
width as the front Hyper 7 arms, I trimmed off about 30 mm for the longest
axle tube. This had the added benefit of making the axle symmetrical, ie
the differential "pumpkin" was now centered on the axle.
In order to mount the upper link
centered to the differential, I needed to mount a pair of barckets to the
sides of the "pumpkin". I did this with some 5 mm 7075 which I milled with
a "slant" that would ensure a flush fit to the slanted sides of the
pumpkin. The mounts where then drilled to fit the exsisting diff housing
bolts.
Milling
the center support brackets.
While working on the brackets on the
diff housing I figured I could try to integrate it with an axle brace. The
brace would "lock off" the steering knuckles, and could help stiffen up
the whole axle. I milled a one piece brace from 5 mm 7075 T6, and drilled
it to fit suitable attachments on each knuckle.
Rear axle
brace.
>
Rear shocks and mounts
Another area that went
through a whole bunch of changes where the rear shocks. Thanks to the
weight of this rig, combined with the required amount of suspension
travel, I tried a lot of different suspension configurations. I had
already provided for the lower shock mounts by designing mounts on the
lower suspension arms. For the upper mounts I started off by simply
mounting a 5 mm bolt that ran straight through the aft end of the
rollcage and front end of the tail section. This gave me a very firm
mounting loction for the shocks, and sorta seemed to work well in terms
of shock angles and such.
The first version was simply me mounting a pair of
long Savage shocks directly to the upper "bolt mount". Length-wise
this worked OK, and did provide the required suspension travel.
However I was never able to find a spring strong enough for this
shock, and I ultimatly gave up on this version.
Version 1 shocks & mounts w/ Savage shocks
In my second attempt I got sorta fancy. Wanting to
use some big reservoir shocks I had available, I decided that I
wanted to run 4 shocks in the rear, mounted in a side-by-side
fashion. To get the angles right, I first milled some upper mounts
that hooked up to the "bolt mount" and the roll cage. I then milled
a lower mount that would fit 2 shocks and fit the mount in the lower
arm. While working fairly OK, this version simply ended up taking
too much space, so this version was ultimatly ditched as well.
Shocks & mounts, version 2.
For the third and final version I used 2 of
the upper mounts I made for the dual shock version, mounted a pair
of long 1/8 buggy shocks w/ VERY stiff springs and BAM - I had the
angles and travel I was looking for.
Shocks & mounts, version 3.
