The 19×9 and 19×12 forged alloy wheels are six pounds lighter up front and nearly nine pounds lighter at the rear, and wear stock-sized 245/35 and 325/30 Pirelli Trofeo Spec tires. The real key to the car’s even sharper handling, however, is a Level 2 semi-race suspension kit that uses fully-adjustable coil-overs, adjustable anti-roll bars, and selected GT3 RSR components. Ride height is set 15-mm lower than stock, but a bump-steer kit brings the roll center back to the proper height using modified tie-rod ends and bushings.
These suspension modifications take advantage of GMG’s bolt-in roll cage made out of TIG-welded, 4130 chrome-moly steel. Its chief advantage over the factory’s Clubsport equivalent is that you can move the lightweight Recaro race seats all the way back if you’re tall. The final tweaks are aerodynamic in nature. While the latest GT3 RS is perfectly stable on the autobahn at close to top speed and pretty effective on track, too, hardcore track junkies will want even more downforce — especially if they’re running slicks. For that reason, GMG added a race-car front splitter and a rear-wing Gurney flap.
Out on track, the suspension changes are brilliant. The car turns in even more incisively, and the lowered chassis — with its race-bred components — makes the RS’s already pointy but stable front end even more aggressive into the turns. The cumulative effect moves the 997-2 GT3 RS a couple steps closer to a Supercup racer. Critically, GMG has managed to maintain the exquisite balance of the stock GT3 RS while taking turn-in response, handling, and mechanical grip a notch higher.
There’s always a cost, though, and the GMG car has traded some ride comfort for greater precision and a greater sense of involvement. Ride comfort is now somewhere between the 997-1 GT3 and 997-2 GT3, but still vastly better than the choppy 996 GT3 RS. For track-day types, one suspects the tradeoff is worthwhile. The steering, in particular, delivers its messages even more crisply, thanks in part to the slight increase in negative camber. The rear end, thankfully, follows the front faithfully into a turn without any nervousness.
Loud pipes aside, this RS is a realistic proposition as a daily driver. Of course, it might be a bit much for anyone this side of the hardest core — and may even be too hard for some real junkies, too. It is, however, the closest thing to a street-legal Supercup car that I’ve tried yet.