As normal, a large portion of the stock electronic gizmos and driving aids were ditched although like its predecessor, the new model was heavier than the Carrera Coupe. Weighing in at 1380kg, this was an increase of 35kg. Springs were 20% stiffer than stock and the body sat 30mm lower, fully adjustable suspension geometry along with equally tuneable ride-height and anti-roll bar settings meaning drivers could tailor their set-up to any given circuit. Brakes were cross-drilled and ventilated discs of 350mm diameter front and 330mm back, new ten-spoke 18-inch alloy wheels being shod with Michelin Pilot Sport tyres. UK and US-spec cars got the standard 64-litre fuel tank, all other markets getting an 89-litre item. Engine-wise, MkII's featured a revised version of the GT1-based 3.6 as used in the previous GT3. Only the outgoing block remained and thanks to the use of many new parts (forged pistons, titanium conrods, lighter valves and smaller tappets) an overall weight reduction of 3.5kg was achieved.

Visually, MkII GT3's were equipped with a new aero kit that improved high speed stability and later become optional on standard 911's. At the front was a subtly re-profiled nose with new duct treatment and a matt black chin spoiler. Hung over the rear axle was an electronically adjustable spoiler mounted above a fixed mini ducktail. The body-coloured side skirts were also subtly revised and new 10-spoke alloy wheels fitted. Inside, the rear seats were junked and there was little in the way of soundproofing, customers being offered two levels of trim. Standard GT3's came with leather-covered bucket seats, electric windows, four airbags and central locking. By contrast, Club Sport variants got competition Recaro bucket seats in flame-retardant fabric with six-point harnesses, a bolt in roll-cage and fire extinguisher. The Club Sport package was a no-cost option. Performance of either derivative was explosive, the GT3 hitting 190mph flat out, 0-60 in just 4.5 seconds and 0-100 in 9.4.