2006 Porsche 997.1 GT3 Cup Car

2006 Porsche 911 GT3 Cup 997.1

List Price: $89,000

Vehicle Overview

2006 Porsche 911 GT3 Cup 997.1 with extensive later-generation upgrades and a documented history of competition use, maintenance, development, and recent mechanical refurbishment.

The car has been actively maintained and developed as a POC/PCA competition car. Major systems addressed during the current ownership period include the gearbox, clutch and flywheel assembly, KMP shifting system, braking system, brake hydraulics, cooling system, ignition system, fuel system, suspension setup, and general chassis preparation.

Key specifications and equipment:

• 2006 Porsche 911 GT3 Cup 997.1
• 997.2-related upgrades
• KMP paddle-shift system
• MCS 3-way dampers
• Three sets of BBS wheels
• Air-jack system
• Garmin Catalyst
• Motorsport fuel pump-out system
• Factory Cup-car roll cage and safety structure
• Michelin Porsche Carrera Cup slick fitment
• Extensive maintenance and competition records

Current engine hours: 81

Current gearbox hours since rebuild: 18

Historical records supplied with the car show approximately 17,000 km on the chassis by late 2024. The engine was reportedly rebuilt before the previous owner’s June 2018 acquisition. The prior owner’s log recorded approximately 54.5 engine hours by late 2024.

Recent Mechanical Service and Development

November 2025, Comprehensive Inspection and Baseline Preparation: Following acquisition, the car underwent a comprehensive mechanical and safety inspection intended to establish a baseline before continued competition use.

Inspection areas included:

• Engine and drivetrain
• Cooling system
• Fuel delivery system
• Brake system
• Steering and suspension
• Wheel bearings and hubs
• Electrical system
• Roll cage and safety equipment
• Chassis and underbody
• Air-jack system
• Harness mounting
• Aero and body attachment points
• Motorsport compliance items

Following the inspection, the car received:

• New spark plugs
• New air filter
• Engine oil and filter service
• New steering-wheel hub
• Rear coolant pipe secured with additional silicone coupler and clamps
• Air-jack hardware secured
• Gearbox/shifter-solenoid hose secured• Crotch-harness repair
• Intake-manifold coupler secured
• Throttle-cable retention work
• Hose, line and electrical management
• Rear-wing mount repair

This work established a known mechanical baseline before the larger drivetrain service that followed.

January 2026, Gearbox Rebuild and Drivetrain Refresh

The gearbox was removed and underwent a comprehensive teardown, inspection and rebuild.

Documented gearbox work included:

• Big shaft nut, input
• Big shaft nut, pinion
• Small shaft nut, input
• Pinion four-point bearing
• Input four-point bearing
• GT3-type floating gear dog ring
• 3rd-gear spline gear, 31:18 ratio
• 3rd-gear dog gear, 18:31 ratio
• 5th-gear spline gear
• 6th-gear dog gear
• Selector ring
• Complete teardown, cleaning and inspection
• Reassembly with replacement components
• Test-rig operation following rebuild to verify operation and noise level

The gearbox was reinstalled with fresh Motul Gear Competition 75W-140.

The clutch system was refreshed concurrently with:

• New Porsche 997 GT3 Cup clutch kit
• New Porsche 997 GT3 Cup flywheel
• New Porsche 997 GT3 Cup slave cylinder
• Clutch hydraulic system flushed with Castrol SRF

Additional work included:

• Six new ignition coils
• New fuel filter
• Brake-fluid flush with Castrol SRF
• Engine oil and filter service
• Fuel pump-out hose
• Air lance
• New Michelin Porsche Carrera Cup slicks
• Alignment and setup

This represents one of the most significant mechanical updates performed during current ownership.

February/March 2026, Brake System and Drivetrain Service

Following additional track use, the car underwent another detailed post-event inspection. The inspection identified wear in the brake system and cooling system along with additional shifting-system concerns. The brake system subsequently received a substantial refresh including:

• New GiroDisc front rotors
• New GiroDisc rear rotors
• New front brake pads
• New rear brake pads
• Rebuilt front brake calipers
• Rebuilt rear brake calipers
• New front caliper rebuild kits
• New rear caliper rebuild kits

This effectively refreshed the major braking wear components at all four corners.

The shifting assembly was also disassembled and inspected, with additional gearbox tail-shaft work performed following the earlier gearbox rebuild.

Cooling-system work included:

• New water pump
• New water-pump gasket
• Coolant-system flush
• Fresh coolant

April 2026, Brake Hydraulic System

Both brake master cylinders were subsequently replaced:

• New front brake master cylinder
• New rear brake master cylinder
• Full brake-system bleed
• Castrol SRF racing brake fluid

A Garmin Catalyst was also installed. The car received another post-event service including:

• Engine oil and filter service
• Air-filter service
• Radiator cleaning
• Brake-disc and caliper cleaning
• Driver compartment inspection/cleaning
• Wheel-nut inspection
• Fuel extraction
• Alignment/setup work

The April invoice confirms the master-cylinder replacement, Castrol SRF bleed, Garmin installation, oil/filter service and broader post-race service.

May 2026, Cooling-System Upgrade and Track Preparation

The cooling system subsequently received another significant update with replacement of all three radiators.

Installed:

• CSF 7053 center radiator
• CSF 3552 left radiator
• CSF 3551 right radiator
• Red Line Water Wetter

The three-radiator replacement addressed the older radiator assemblies following previous observations of fin damage and buildup.

The car also received:

• Post-event inspection/service
• Engine oil and filter service
• Air-filter cleaning
• Brake-disc and caliper cleaning
• Radiator-area cleaning
• Wheel-nut inspection
• Fuel extraction
• Alignment/setup work
• Michelin Pilot racing slicks
• Touchless tire mounting
• Road-force balancing

Historical Service and Development

The car includes maintenance and usage records predating current ownership.

Documented prior work includes:

• Engine rebuild reportedly completed before June 2018
• Clutch and LSD replacement, June 2020• Engine oil service and clutch bleed, August 2020
• Replacement clutch, April 2021
• Engine-seal replacement and transmission-seal inspection, May 2021
• Front brake-caliper rebuild, August 2021
• Wider front-track/setup changes, March 2022
• Gearbox rebuild/replacement cycle, 2022
• KMP paddle-shift system rebuild/service, January 2024
• KMP service included the main gearbox unit, three cylinders and pump

The historical log documents use at Buttonwillow, Willow Springs, Chuckwalla, Laguna Seca, Thermal, Streets of Willow and Auto Club Speedway.

Fuel Cell

The car is equipped with a Harmon Racing Cells FIA FT3-1999 fuel-cell bladder.

Documentation identifies:

• Harmon Racing Cells
• FIA FT3-1999
• Serial No. 12186
• Manufacture date: July 2019
• Original certification expiration: July 2024

Fuel-cell documentation is included with the car.

Competition History Under Current Ownership

The car has continued to see active West Coast track and POC competition use rather than long-term storage.

Development and competition use have included Buttonwillow, Willow Springs and Laguna Seca, with continued chassis setup work performed throughout the season.

At Laguna Seca, the car recorded a 1:34.943 race lap while competing in the POC GT2 field.

Current Mechanical Status

The car has received extensive recent mechanical refurbishment across the drivetrain, brake system, cooling system and supporting race systems.

During the most recent Laguna Seca race weekend, an intermittent gear-selection/reverse issue developed. The shifting and gearbox system is being assessed before sale.

Final current gearbox condition and current component hours will be supplied following inspection.

Records

Extensive maintenance and service documentation is available with the car, including:

• Historical engine-hour records
• Historical gearbox-hour records
• Track-use logs
• Gearbox rebuild documentation
• Recent service records
• Fuel-cell documentation
• Inspection records
• Setup and maintenance history