Choice between a Porsche 997 GT2 vs. GT3 vs Turbo
Killer-M | On 20, Dec 2012
We got a few owner-experts and one semi-professional driver to test out a stock 2007 Porsche Turbo, another equipped with after market Bilstein coilovers (and other goodies), a 2008 GT2, and 2010 Porsche GT3. Switching back and forth between all four cars for about 3-4 hours in twisty canyon roads – we all reached some interesting conclusions.
Unless you switch to R comp tire like Pirelli Corsa, and modify your suspension to something stiffer than aftermarket springs (H&R, TechArt, etc.), adding sway bars, and change your alignment to more negative camber, there is simply no comparison between GT cars and a stock Turbo, especially in very tight corners. Both GT3 and GT2 Porsche’s would easily out corner, out stick, just generally out handle a stock Turbo.
So we listed some changes to the 997 turbo that will close the gap dramatically and provide a more comparable, yet fun driving experience, and a perfect compromise between the daily driver turbo and a track ready GT Porsche.
Porsche Turbo, GT2 and the GT3 – making the decision between three supercars
Lets face it, the GT’s and the Turbo are totally different from one another when it comes to ride and handling. Although they share a lot of similarities, the chassis with different tweaking. Despite of its reasonably fast ‘Ring time, subjectively the stock Turbo to me is a very boring and lazy car, way too soft, way too mushy, and with lazy steering (GT’s steering is razor sharp).
The bottom line is that there is never going to be a perfect answer or a perfect solution to the ride vs. handling dilemma. The GT’s are about handling, the Turbo about ride, and a modified Turbo is about ride and handling mix.
I have a 2007 turbo and have gone to a GT2RS suspension set-up (including increasing wheelbase, widening the front track, the active suspension module from TPC Racing and a Limited Slip Differential). That combined with an aggressive alignment makes the car feel almost like a GT2, except that the PASM is still programmed for an all wheel drive so as close as the handling is, you can tell it’s AWD vs. the GT2.
The Stock turbo, for street driving, it works really well. It’s clearly build to be a car to blast around on the Autobahn as opposed to ripping out lap after lap around a circuit, where the GT3 shines. The GT2 can do both but at the sacrifice of street civility.
It all comes down to suspension setup
GT2 has a more aggressive aerodynamics package, it has sharper and more communicative steering, the engine is still the good old Porsche Mezger 3.6 liter, but with some improvements, and of course offers pure rear-wheel drive. More importantly a massive 150kg (250-300 lbs) weight saving over the all wheel drive Turbo.
If you’re not planning on tracking the car, would the weight difference and the softer handling setup really matter? On the street you’re not pushing the TT to it’s handling limits anyway (and if you are, seriously, consider tracking as a safer alternative). So the performance difference between the TT and GT2 should be almost a moot point (or at least should be if you’re driving like a sane person).
The GT3 has even sharper steering than GT2, less mass than GT2 and generally is a better sports car – although slower in a straight line and out of the twistiest.
…but I love the punch of turbos.
A Bilstein Damptronic adjustable coil over equipped 997TT, with a GT2 rear sway, Tarett Engineering drop links, and alignment has a very similar profile to a stock GT2. Power levels were provided straight line acceleration were also very similar to a GT2 in terms of trap speed and in typical street conditions, even with aggressive driving, the Turbo handled very similarly. Out of the box, the GT2 still has a large amount of understeer, but it is correctable with proper alignment.
On the street, a GT2 rides fine – similar to a Bilstein equipped 997TT – somewhere between sport mode on and off.
GT3 is the “purer” and better handling car, and the ultimate track weapon. (If you follow track times of identical courses of the 2 cars, in some corners the GT3 has higher speeds.) It’s not going to be an easy decision there either.
After market suspension recommendations:
1. Bilstein PSS10 mono-tube dampener and dual spring setup, with a height drop of approx. 10 mm
2. Street GT3 alignment, meaning a change of front camber from -.4 to -1.2.
3. GMG, RSS or GT2 anti-sway bars; set to full soft front, medium stiff rear.
4. RSS solid engine mounts (make a dramatic difference in reducing the “moving mass” of the rear engine feel)
5. Rear drop links (Tarett engineering)
6. Rear toe control arms
Check out the current 2007 Porsche 997 Turbo, our current suspension project.