With the stiff stuff handled we also wanted to focus on bushings and roll bars. For the front we we knew we needed to obtain more positive caster and correct some bumpsteer issues, we also wanted to add an adjustable larger front sway bar. For the caster improvement we turned to none other than the good folks at Global Performance Parts and Whiteline suspension. They supplied us with their KCA303M caster bushings. These motorsport durometer urethane bushings replace the OEM control arm bushings and increase caster by moving the rear most portion of the control arm outward.
|Whiteline offers their caster bushings in two different durometers. We chose the harder “motorsport” bushing.|
We turned to a company by the name of Bolt in Bars for the bumpsteer correction! They manufacture a kit that replaces the factory tie rod end with a heim joint, the kit includes a spindle that allows you to raise or lower the mounting point of the tie rod end to level the tie rods. While the kit works very well a potential improvement would be to opposite thread one half of the coupler that threads on to the inner tie rod. This design change would allow for even more toe adjustment at an easier to reach location than the inner tie rod.
|On a lowered car having the tie rod above the spindle contributes to bumpsteer issues.|
The car as it stood was somewhat twitchy at high speeds and we really needed a larger front swaybar to improve stability. We chose the Progress 30MM adjustable front swaybar to hlep us dial in some confidence in that area. It is 3 position adjustable and uses heim jointed endlinks in place of the silly putty like OEM bushings. One area that took some sorting (read: serious fu@*%^g with) was the tabs on the front bar. Because our tie rods were moved lower; at full droop and full lock they wanted to occupy the same real estate as the sway bar tabs. NO BUENO… We had to grind a SERIOUS amount off the tab of the swaybar as well as use spacers under the U clamps at the chassis. This moved the bar lower to give us more room and at the same time it reduced stiction on the swaybar. Despite the fact that the bar sits lower it should offer better performance and less chance of binding. Again this area took a bunch of grind, test fit, grind, to get right. Honestly I am glad it is sorted….
|No more suck. The bumpsteer kit allows you to relocate the tie rod underneath the spindle allowing you to get the tie rod parallel to the control arm, thus greatly reducing bumpsteer.|
With the front buttoned up we stuck our heads under the rear…. well err. We turned our focus to the back of the car. Here we used the Stillen adjustable rear sway bar. The Stillen bar is the largest rear swaybar on the market (29MM) without entering the Kojima-san custom raceway bar setup. It is a nice piece featuring CNC aluminum brackets to mount to the trailing arms and is adjustable. Another point to note is that the OEM rear beam is built with toe in from the factory. We previously had the rear beam bent to zero toe by the Nissan community’s resident expert, Steve Foltz. Steve uses a jig to support the beam during the bend. This is a critical modification on ANY Nissan that uses the rear beam.
|Our completed rear suspension assembly. You can see the Stillen rear swaybar brackets as well.|
|While we were at it we installed Stillen’s strut tower braces. For the front bar we used these custom Three14 motorsports adapter brackets as the Stillen brackets will not work with the Ground Control camber plates.|
After dialing in the alignment settings we set out to test the suspension we just built. The first thing we noticed was how comfortable the car rode. Honestly it is damn close to factory. It does not ride like a lowered car at all. It feels tight and connected, but is almost cushy. For a street car this is the ideal suspension! You really can get the best of both worlds, a decent track setup and a comfortable street ride. After enough street BS we hit the track as soon as possible. We noticed huge improvments. The car is much more neutral and the tail end follows around nicely. The car is more stable at high speeds and feels much more planted. What amazed us the most is how the car remains stable even if getting slightly upset mid corner by a bump or rumble strip. BIG difference over the previous setup! It is harder to get the car to understeer. It is more comfortable at the limit and has left us wanting more out of it. Given that the project is making it’s way towards a dedicated track and time trial car we have to analyze if we will be able to run enough spring on these dampers. Regardless one would be hard pressed to find a better suspension for a dual purpose vehicle. You could truly drive this car daily and go destroy the track on the weekend! What seals the deal is Koni’s unbeatable service and reputation for quality!
This project would not have been possible without our sponsors:
KONI North America
1961 International Way • Hebron • KY • 41048
Telephone: (859) 586-4100
Ground Control Suspension Systems
3885 Dividend Drive – Shingle Springs – CA – 95682
Telephone: (530) 677-8600
Global Performance Parts
U.S. Distributor for:
4554 128th Avenue – Holland – MI – 49424
Telephone: (616) 399-9025
The Progress Group Inc.
1265 N. Grove Street – Anaheim – CA – 92806
Telephone: (800) 905-6687