Drivetrain upgrades for the MGB GT V8 cover gearbox conversions and clutch upgrades. The factory four-synchromesh gearbox with overdrive provides effectively five forward ratios (four direct gears plus overdrive on third and fourth), but a true five-speed gearbox conversion offers a closer-ratio set with the convenience of a single shifter rather than a separate overdrive switch. Performance clutch components address the higher torque output of capacity-upgrade engines.
Five Speed Conversions
Five speed gearbox conversions replace the original four-synchromesh gearbox plus overdrive with a five-speed manual gearbox unit. The conversion provides closer ratios across the gearset and places the fifth-gear ratio under direct shifter control rather than via the overdrive switch. The conversion involves the gearbox itself, an adaptor bellhousing to mate to the V8 engine, modified gearbox mountings, a propshaft of revised length, and the speedometer drive arrangements appropriate to the new gearbox. Full kit details are listed under the Five Speed Conversions sub-section.
Performance Clutch
Higher-output engines, capacity-upgrade engines or significantly modified standard 3528cc units, produce more torque than the standard clutch was designed to handle. Performance clutch options include uprated friction discs, higher-clamp-load pressure plates, and complete heavy-duty clutch kits. The appropriate level of clutch upgrade depends on the engine specification, the parts team can advise on suitable specifications.
Sub-Sections
Five Speed Conversions covers complete five-speed gearbox conversion kits.
MGOC Spares
MGOC Spares supplies drivetrain upgrades for the MGB GT V8, see individual sub-sections for details.