GT3 RS (991)

For a car built for the circuit, the most useful first changes are about consistency rather than power: high-boiling brake fluid and suitable track pads, a geometry set-up matched to how you use the car, and good tyres. Seats and harnesses that hold you properly come next, followed by lightweight forged wheels. Exhaust and intake upgrades mainly add sound and response, so most owners treat them as a later step.

The naturally aspirated 4.0-litre flat-six is already highly developed, so software and bolt-on gains are modest compared with turbocharged cars. Exhausts and intakes typically bring sharper response, a little weight saving and more sound rather than large power increases. Most owners find lap times improve more from tyres, alignment, brakes and driver tuition. Any engine work should be carried out by a Porsche GT specialist.

The early 991.1 GT3 was recalled for engine replacement after connecting-rod bolt failures, and a later finger-follower defect led Porsche to extend cover to a 10-year, 120,000-mile engine warranty on the 991.1 GT3. Porsche stated the finger-follower issue did not affect the 991.1 GT3 RS. Even so, a specialist pre-purchase inspection, including an over-rev report and service history check, is wise on any GT car.

Yes, but they must be made specifically for Porsche's centre-lock hub, with the correct offset and load rating for the 991 GT3 RS. Centre-lock nuts need a calibrated torque wrench, the correct socket and the specified lubricant on the threads and contact faces, and Porsche specifies a very high tightening torque. Many owners have wheel changes done by a specialist, and fitment should always be confirmed for 991.1 or 991.2 before ordering.

Harnesses are designed for circuit use and need correct mounting points, such as the Clubsport rear bar, plus the right shoulder-strap angle to work safely. For road use, keep the factory three-point seatbelts fitted and working, because they are what the MOT inspects and what airbags are designed around. Declare harnesses and aftermarket seats to your insurer, and have them fitted by someone experienced with GT cars.

Some will, but the two generations differ more than they look. The 991.2 has a different 4.0-litre engine, revised front bumper and aero, ball-jointed suspension links and front helper springs, so exhausts, intakes, aero and suspension parts are often generation-specific. Seats, harnesses and fluids are more likely to carry over. Check the fitment shown on each R44 product or ask our team to confirm before ordering.