XYZ Racing Circuit Master Coilovers — Subaru IMPREZA STI GRB/GVB/GRF/GVF 4WD 2007-2014

The GRB/GVB hatch and GRF/GVF saloon share a trait that defines how they need to be sprung for track use: a 4WD driveline that adds mass low and centrally, changing how the chassis loads under trail-braking into a corner compared with a front-drive equivalent. Circuit Master is the XYZ Racing coilover built for exactly that scenario – sustained lap-time work where damping consistency across a session matters more than outright ride comfort.

For an Impreza STI that’s doing repeat sessions rather than the odd trackday, the priority shifts from one fast lap to holding a setup as tyres, brakes and the car generally heat-cycle through a run. This is a coilover for owners chasing that consistency, not a fast-road compromise dressed up in a circuit name.

What this coilover does for your 2007-2014 Subaru Impreza STI Grb/gvb/grf/gvf 4WD

With 9720 combinations of damping adjustment on offer, you can set the STI up to control body movement through direction changes without transmitting every surface imperfection into the cabin – useful given how much weight the AWD hardware puts through the front subframe under trail-braking. The 3-knob adjustment layout means compression and rebound can be separated out per axle, so you can tune the rear to stay planted under power out of a corner while keeping the front responsive to turn-in inputs. Monotube-style damper construction resists the heat build-up that comes with back-to-back laps, which matters on a car already carrying extra rotational mass from its drivetrain. The result on track is a chassis that changes direction with less of the pitch and squat that stock Subaru dampers allow, and a platform that keeps its damping character consistent from lap one through to the end of a session rather than fading as the oil heats up.

About the Circuit Master coilover

Circuit Master sits at the top of XYZ Racing’s range, developed off the same platforms used in Racing Spec, Drift Spec and Tarmac Rally applications and run by XYZ-affiliated racing teams on circuits internationally. The core idea is adjustment depth: 9720 distinct damping combinations give a tuner enough range to match spring rate, compression and rebound to a specific car, driver and circuit rather than living with a single fixed compromise. Each unit uses a 3-knob external adjuster design with a small-orifice oil circuit, which is what delivers that granularity of control. One side effect of the small-passage design is that oil movement through big compressions – kerbs, ripple strips – can produce a faint noise; that’s a normal characteristic of this valving, not a fault, and it’s not something the coilover is bothered by. Construction is aimed squarely at circuit use, built to take repeated bump loading from track surfaces without the oil circuit or seals being a weak point over a session.

Fitment for the Subaru Impreza STI Grb/gvb/grf/gvf 4WD (2007-2014)

This Circuit Master kit is built for the Subaru Impreza STI GRB/GVB/GRF/GVF 4WD, chassis code SU10, covering the 2007 to 2014 model years across both hatchback and saloon body styles. It’s specified for the 4WD drivetrain these chassis codes share, so confirm your STI matches this chassis-code range before ordering.

What buyers also search for

• Subaru Impreza STI coilovers for track and fast-road use on the GRB/GVB/GRF/GVF chassis
• Subaru Impreza STI adjustable damping that holds its setting across repeat lap sessions
• XYZ Racing Circuit Master coilover options for 4WD Subaru STI circuit builds
• Subaru Impreza STI suspension upgrade for GRB hatch and GRF saloon owners tracking their car

Spec your Circuit Master to your STI’s setup and configure yours below.