The new models will feature the 296bhp 2.0-litre flat four used in the base Cayman and Boxster models and a six-speed manual gearbox, with a number of performance-inspired tweaks alongside the chassis, which is 20mm lower than standard.
The engine has 280lb ft of torque and allows both cars to achieve 0-62mph in 5.1sec, with a top speed of 171mph. Each car weighs 1350kg.
The T designation stands for Touring, which Porsche uses for vehicles with “dynamic driving performance”.
The changes include new dynamic gearbox mounts alongside the active drivetrain mounts, which Porsche says increase precision and stability. Porsche’s torque vectoring system, which features a mechanical rear axle differential lock, is included, with a dual-clutch PDK transmission available as an option.
Other changes include a shortened gearshift, 20in titanium grey alloy wheels and the Sports Chrono pack. To save weight, neither model includes an infotainment system – with a storage compartment in its place – although customers can choose to spec one as a no-cost option.
Externally, the T models are also differentiated by grey mirror shells featuring logos, and a twin-tailpipe central sports exhaust finished in chrome.
Interior additions include unique trim featuring black door pulls in the panels and electronic two-way adjustable sports seats with the 718 logo embroidered on the headrest. The cars also get a 360mm GT sports steering wheel, with Boxster T or Cayman T logos on the instrument dials.
Prices for the 718 Cayman T start from £51,145, with the 718 Boxster T starting at £53,006.