No It’s Not an STI: GST Motorsports Mighty Subaru Impreza

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No It's Not an STI: GST Motorsports Mighty Subaru Impreza
Stock STI rear Brembo two piston calipers are used with Giro Disc two piece floating rotors.
No It's Not an STI: GST Motorsports Mighty Subaru Impreza
Alcon 4 piston calipers are used on the front brakes with a 340mm floating two piece Alcon rotor.

Braking is handled by Alcon Monoblock 4 piston calipers and big 340 x 32mm Alcon floating rotors in the front with Brembo 2 piston rear calipers with Girodisc two piece rear rotors.  Endless brake pads provide stopping power with Endless brake lines giving a firm pedal.  A Tilton 600 dual master cylinder pedal box, balance bar and master cylinders handle mechanical brake proportioning.  Hydraulic proportioning is adjusted by a Tilton prop valve.

No It's Not an STI: GST Motorsports Mighty Subaru Impreza
Tilton Proportioning valve controls the hydraulic aspect of the proportioning, a prop valve controls the line pressure after a knee point.  This helps reduce rear wheel lock up after braking starts and weight is transferred.

The transmission is super trick.  It is a Modena Engineering Guard six speed with super fast shifting dog engagement gears and sequential shifting.  The gears are selected via a Kartboy short shifter.  The front, center and rear differentials are all mechanical units from Modena as well.  Power is fed to the tranny via an ACT lightweight ProLite steel flywheel.  An ACT Extreme pressure plate with a single 6 puck sprung hub disc clutch transfers the torque.  It is amazing that this relatively conventional clutch can reliably hold all of this power.  A custom carbon fiber drive shaft feeds the power to the rear wheels.

No It's Not an STI: GST Motorsports Mighty Subaru Impreza
A Tilton 600 pedal box is top hung so you can't see it too well.  This controls the slope of the brake proportioning curve.  You can see the Hydra Nemesis ECU, switch panel, master fuse panel, AIM dash, and sequential shifter and OMP steering wheel here.
No It's Not an STI: GST Motorsports Mighty Subaru Impreza
The Safecraft on board fire system is important for safety.
No It's Not an STI: GST Motorsports Mighty Subaru Impreza
Dry cell battery saves weight and won't spill corrosive electrolytes.

Of course a Time Attack car's suspension is very critical and the GST car has a lot of the best.  JRZ Triple adjustable dampers are wrapped by Swift Springs, 650 in/lb front and 550 in/lb rear.  Whiteline 27mm adjustable anti swaybars are used front and rear with Whiteline spherical end links.  A Whiteline anti lift kit reduces the front anti for more traction under braking and on-throttle.  A Whiteline roll center and bumpsteer correction kit is also used on the front end.  Cusco lateral and trailing links give the rear adjustability.  All bushing are replaced by GST with spherical bearings.  Finally the track on the car has been widened 1″ per corner.

No It's Not an STI: GST Motorsports Mighty Subaru Impreza
The roll cage does a lot to stiffen the chassis.  A HANS compatible Racetech seat provides head protection.

 

No It's Not an STI: GST Motorsports Mighty Subaru Impreza
JRZ three way adjustable remote reservoir shocks are used all around.
No It's Not an STI: GST Motorsports Mighty Subaru Impreza
Whiteline adjustable swaybars are used (part numbers BSF20Z, BSR20XXZ).  You can see the extended shank on the tie rod to help correct bump steer.  You can also see the extended shank ball joint which corrects the front roll center.  The bibs for the brake ducts are visible as are the Swift springs.

 

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