On October 30th, as the automotive world worked tirelessly to prepare for the biggest event of the year--the SEMA show--I too was caught up in a time crunch, wrenching on my Subaru STI... but for a different reason. The STI had just returned from a shakedown session at Buttonwillow Raceway in preparation for our Nov 11th Import Tuner STI vs. EVO shootout. The car ran well, but was hardly track-ready as I scrambled from shop to shop, attempting to gather the necessary components to make the deadline for competition. Since I was selected to be one of five car owners representing the Subaru class, I'd better be damn sure that I was prepared to wage war.
Recap Buttonwillow Raceway Shakedown
NASA held an open invitation track day at Buttonwillow Raceway, using the Super Lap Battle clockwise configuration CW13. The car encountered continual issues with the charge pipe blowing off after every lap, and its 235/35-18 tires had a slight rubbing issue towards the rear fenders, but nothing to be too concerned about. The STI showed signs of slight understeer, but with some minor adjustments we were able to induce the rear to slide out. My driver for the day--and for the upcoming STI vs. EVO shootout--was none other than in-house wheel-man Andy Hope who, after a few laps, stated "the car's a handful and slides all over the place... but is fast as shit, and totally predictable on the track!" The feedback was promising as the TEIN engineers helped me continuously throughout the shakedown sessions, making minor adjustments to the toe and caster settings before calling it a day.
Day 01:Sunday Nov. 2
The early morning began with some routine maintenance and replacing of engine fluids. The brake pads were replaced with a set of Hawk HP+ and stock fluid was bled for Motul. In anticipation of using this aggressive street/race pad, I picked up some silicone brake duct hose to install onto the car's Chargespeed carbon fiber brake ducts. If you noticed in our previous photos from the shakedown session, the STI was lacking aerodynamics, which included missing side skirts and a rear wing. With the help of Chargespeed, we were able to acquire a full body kit along with a pair of larger 20mm front fenders. Finish Line Auto Craft in Gardena, CA sprayed it factory Aspen white, while I ran back home to continue piecing the car together. The factory rear wing was re-attached on a carbon trunk to promote more rear down force. Without the wing, the STI's balance seemed to be upset; the rear end was a bit too squirrelly through the turns.
Day 02: Monday Nov. 3
Whiteline suspension played a major role in getting the vehicle to its current status as many of the parts began to roll in one at a time. I began working on the front of the car and made my way back. The first items to tackle were the Whiteline anti-lift kit, steering rack bushings, and roll center adjusters. With a simple upgrade of these three items, a noticeable difference in handling performance can be felt on the track. The Whiteline transmission cross member bushing was also easily swapped in within minutes.
Day 03: Tuesday Nov. 4
I begin with the installation of the Whiteline front and rear 27mm sway bars. While many suggest this diameter is too aggressive for the STI, we found that using larger-diameter sway bars with bigger tires creates more oversteer and brings the STI's rear end around like a RWD vehicle, remedying understeer problems most AWD vehicles suffer on the track. Both front and rear sway bars were matched up with a set of spherical bearing end link kits to tighten up the suspension.
Day 04: Wednesday Nov. 5
In a quest to further stiffen the chassis, I paid a visit to M1 Fabrication & Development in Brea, CA, to pick up a chromoly sub-frame brace. The lighter and more rigid brace uses the factory pickup points and easily bolted into place. Not only does the brace aid in stiffening up the chassis, but it brings the vehicle's front-to-rear weight ratio to a more even level. With some skillful body contortion, I was able to mount and bolt the sub-frame brace onto the car using jackstands.