Energy urethane trailing arm...
Energy urethane trailing arm bushings take much of the gush out of the rear suspension.
Whiteline's roll center adjustment kit was also installed in the front suspension. This unique and innovative product makes an EVO handle well. We're used to hand fabricating this sort of part on our racing cars, but Whiteline simplified it by making it a bolt on product for the EVO. The roll center adjustment kit uses a ball joint with a longer shank. This effectively moves the lower control arm outer pivot downward and raises the roll center. In a lowered car, the roll center drops and the roll couple, which is the lever arm for centrifugal force to roll the car over, gets longer. Thus a lowered car often exhibits more body roll than a car at stock ride height all other things being equal. The Whiteline kit is designed to move the roll center close to the stock location even on a lowered car.
Whitelines's bumpsteer kit...
Whitelines's bumpsteer kit relocates the rear toe arm inner pivot upward, which reduces bumpsteer in the rear suspension.
On a McPherson strut car, if the car is lowered so that the lower control arms are at an angle of more than 90 degrees to the strut itself, the suspension will gain positive camber under roll. This is terrible for grip and handling. The Whiteline kit helps reduce this effect, further improving handling. Unfortunately, changing the location of the pivot in relation to the tie rod ends can create a lot of bumpsteer. Whiteline cleverly included tie rod ends with longer shanks in the kit to keep the tie rod location in line with the new lower control arm pivots. Now you can do this former race car-only mod for a surprisingly low price. What used to require over a $1,000 of specialized parts and custom fabrication to accomplish is now a relatively inexpensive bolt on. If all of this sounds confusing, quite simply, the roll center adjustment kit will reduce body roll and improve front grip without increasing the spring or sway bar rates.
For the rear suspension, we kept most of the EVO's stock control arm bushings because they are high-quality bearings rather than the soft rubber found on most stock cars. We replaced the soft rear trailing arm bushing with a hard Energy polyurethane piece. We also used Whiteline's rear bumpsteer elimination kit. This kit uses an eccentric bushing to replace the inner pivot bushing of the rear toe arm. The eccentric is used to locate the pivot location downward. This reduces bumpsteer in a lowered car. Reducing bumpsteer gives the rear of the car a more secure feel at the limit, especially over uneven pavement.
You can see how the inner...
You can see how the inner pivot is higher than the stock when the bushing is installed in the car.
Power modded EVOs tend to develop wheelhop when launching from a dead stop or when accelerating out of a tight turn. Much of the wheelhop is caused by bushing deflection in the drivetrain. We installed Energy Suspensions urethane bushings in the rear moustache bar and front differential mount. These soft rubber bushings mount the rear differential to the chassis and replacing them with harder urethane reduces the likelihood of developing wheelhop and breakage of the axles, transfer case and rear differential. We noticed a very slight increase in gear noise from the differential but this was to be expected.
Energy replaces the rear mustache...
Energy replaces the rear mustache bar and differential bushings with hard urethane to help reduce wheel hop.
Finally, we added Whiteline's front and rear adjustable sway bar endlinks. These parts use solid spherical bearings to couple the sway bar to the suspension control arms. This assures that every bit of suspension movement is coupled to the anti-sway bar. This helps sharpen response in a very feelable way. Now the EVO uses a plastic ball and socket endlink stock, which is better than your typical rubber-mounted endlinks. However, the beefy Whiteline parts can better take the stress of the big Robispec bars. Another important feature is that the Whiteline endlinks can be adjusted for length. This allows the user to adjust the length of the endlinks when the wheels are on the ground after the car has been cornerweighted to take the bind out of the sway bar. This assures consistent handling from right to left. As a final nice touch, the Whiteline bits have rubber dust shields to help the spherical last longer in the sometimes hostile street environment.