2025 Q4 Review - Hillclimb Car

The main priority after the sprint at Castle Combe was to change the hillclimb car's turbo position to a less vertical position, to ensure that the bearings would receive enough oil, and to allow re-routing the intake piping to take in air from the wing. Profab exhausts were brilliant as usual with their top notch exhaust fabrication, and soon enough the turbo was in position. This position was different to a rotated setup, which is a common position for larger turbos to be positioned on Subarus, as the turbo was still parallel to the car's centreline but moved back towards the bulkhead which is possible when using an external wastegate as the turbine housing is smaller than the standard housing.

Fitting the new up pipe and the turbo wasn't an arduous process due to the v-band flanges used. The next task after fitting the turbo was to re-route the intake pipe and air filter, as the air filter's high position led to high intake air temperatures when queueing. Routing the intake pipe was made easier due to the Process West intake manifold's intake runners, which are a smaller diameter compared to the standard intake runners. The air filter was mounted within the wheel arch, and a flexible intake pipe was trialled to connect the turbo intake to the air filter. We will report back regarding how this pipe will perform under boost, but seemed to hold up fine during a test drive. Unfortunately the season's final sprint at Castle Combe was missed, but we will be back in 2026 with a some other winter upgrades for the hillclimb car!