Team America World Time Attack – ARK Design’s BNR32 Skyline GT-R Intro Part 2


People think I hate Hellaflush and fitment when in reality I love good fitment with big wheels and tires totally filling out the wheel well. Tires tucking and a cool wheel with a lot of lip is yummy.  I just don't like compromising performance to get the perfect fitment.  When you have control over a lot of the design you can get perfect fitment and total function.  Credit card clearance bitches!
A quick look at the overall front suspension design.  The lower control arm is nice and long to avoid drastic angle changes and reduce side scrub. Besides reducing the motion ratio change over stroke, having the front damper attach to an outboard point on the lower control arm means that the stress on the lower arm is less and it can be built lighter. The upper control arm is 2/3's as long as the lowers to provide good camber gain for radial tires.  A Speedway engineering/Genesis Technologies antiswaybar is going to be used, again, mounted fairly outboard to reduce stress on the arms and so a lighter bar and hardware can be used.  A rotating blade adjuster is going to be used so we can make the bar driver adjustable.  We have a scrub radius of 15mm and a front roll center about 2.5″ above the ground.  The lateral instant center is now 110″ from the wheel centerline vs about 25″ like it was before!
To get our desired upper control arm length, Gary cut into and boxed our frame rails to inset the inner pivots. This system was designed so that it could also be bolted in double shear with the simple addition of spacers. What you cant see are tube tunnels to access the pivot bolts.  The camber curve, anti lift/dive and roll center height can be adjusted with spacers on the pivot mount bolts.  All pretty cool stuff.
A close look at one of the completed points.  Gary reinforced the openings and fully boxed the interior with tube reinforced access holes so the frame rail is probably not weaker than stock despite all the disruption.  After the inner pick up point positions are set, we can change them to double shear with the addition of spacers. Caster, kingpin angle and camber can be adjusted by screwing the inner bearings in and out on the upper arm.  The outer upper arm bearing adjusts camber.
This tube was used for mock up until Genesis delivered the sway bar.  It will also be structural, imparting stiffness to the front end.  You can see details of the lower control arm mounting points and the lower subframe.  The whole assembly unbolts which will speed engine and drivetrain serviceability.  This stuff is light and much stiffer than stock!
A closer look at the swaybar mounting tube.  The engine will be solidly mounted to the lower subframe where it will be semi structural to further increase chassis stiffness to a minor extent.


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