Car: 2005 Subaru STI
Cage: NHRA 8.50
Chromoly Other Goodies: Tubular front and rear cradle with for 8.8 IRS, TSS/custom front SLA, Twin Turbo LS, Tubular front clip, light weight race steering column.
It was 2018 when this car first came to us. It was a referral by our friends over at JM Automotive, who built the 900+ hp EJ25. The owner's goal was mid 8's so we built an 8.50 cage from 4130 chromoly. A custom firewall was also fabricated and properly sealed to make his fuel cell install legal.
A year later, it was back to lose some weight and improve the launch. We scrapped the factory dash, steering column, and crash bar and hung a lightweight race column from a dash bar added to the cage. It saved 12.6 lbs and made the cage safer. He also wantted to add a handbrake to the car, being it was still a manual. We drew up and laser cut a hand brake bracket to bolt to the shifter boot holes. Now he can stage much more consistently.
Race cars are an ongoing project. Return #3 was major surgery. It started with a tube front tied into the A pillar bars of the cage, and a motor plate to house the new LS. A v8wrx.com cradle was bolted in, as well as the transmission crossmember. We did slightly modify the trans crossmember and beefed up the mounting point to make sure it would hold the stress. A set of 76mm Precision turbos were mounted and the induction piping began.
With the Macpherson strut suspension gone, we installed a prototype SLA that the owner of the car got his hands on from TSS Fab. Being the upper arm setup wasn't intended to work with the particular cradle and lower arm setup, we had to scrap the upper arms and make a set of our own. Their kit came with a set of Mustang 2 spindles so we had to cut the provision for the Subaru ball joint out of the lower arm and put a Moog 722 cup in.
Now for the good part. The twins were plumbed in as-perfect-as-possible symmetry, with the air to water intercooler mounted inside. In order to make the whole system serviceable, the area of the firewall that the boost piping passed through was made as a removable panel. The firewall and cowl were cut and a frame was fabricated to house the threaded inserts. A grommet seals the throttle body and the couplers are bonded to seal the opening as per NHRA rules. The exhaust routes through 3" dump pipes out the fenders when the boost valves are open, other wise 2.5" pipes go 2 into 1 and out the factory exhaust location. In order to get the dump pipes out the fenders, the firewall to be cut for clearance. The holes were cut in the headlights by the customer before the project started, which is why they don't line up with where the turbos wound up being mounted.