Project DBA R35 GT-R: Putting the Suspension All Together With SPL Parts and Whiteline
Now we are in the home stretch for upgrading our GT-R’s underpinnings with our quest to improve its on-track staying power and to reduce its propensity to understeer. In previous editions, we did the suspension basics and upgraded the brakes on the car. Now it was time to finish this part of our project off.
One of the keys to getting a car to handle well is to get it to use all of the tires’ contact patches under cornering load. The GT-R has an issue to where the front camber and caster is not adjustable from the factory, and being able to add more negative camber in the front is critical to reducing understeer.
Being able to increase negative camber and keep the caster in check as well is also critical. Really wide tires do not like an excessive amount of positive caster, so being able to adjust the caster is important as well.
We will also be adding more adjustment capability in the rear suspension and getting rid of squishy rubber, so read on to see what we did!
Read more about Project GT-R!
The SPL Parts upper arm is CNC-machined from 6061 T-6 billet aluminum. The arm was designed using FEA (Finite Element Analysis) to assure that the arm would be both stronger and lighter than stock. The arm itself is hard anodized for durability and corrosion resistance.
The bearings ride in 4130 chromoly adjusters that support the entire bearing shank to reduce the chances that they can bend. The adjusters allow the camber and caster to be adjusted quickly without removing the bearing from the chassis side greatly speeding set up time. A 6061 lock ring keeps the adjuster from moving once they are set.
The adjusters are electroless nickel plated for extreme corrosion resistance and smooth operation. All hardware on the arm is lightweight and corrosion resistant titanium.
You can also see the sturdy FK ball joint with its high misalignment spacers that allow a lot of safe articulation over the suspension’s stroke. We should have weighed the arm and gotten an exact comparison to the stock part, but by hefting, it was considerably lighter.
