I posted this question to the 996TT members also.
Is there a marked difference in the handling between a 997S and a 996TT?
I test-drove a 2003 996TT with new Michelin Pilots on and it had a slight "sway" at high speeds. According to friend who owes a 997S, the 996TT did not "grip" the road as well as the 997S did.
I would love the input of the forum.

 

There is a tremendous difference. I assume you know that the 996TT is AWD. It has a completely different feel and driving characteristic. Go test drive a 997S.

 

That's interesting. Your experience is the exact opposite of mine. Not that the 997S is not stable at high speed, but I felt that my 997S front end felt lighter at higher speed. The 996TT that I drove felt like it is on rails all the time, even at high speed. It is so stable that I actually felt "bored" and ended up not buying one.

 

I, too, believe that Porsche made a lot of changes to the 997 suspension from that of the 996/996TT. When I had my 997S up in max speed area (~180 mph) it was very stable. Of course, I had some weight (luggage) in the front trunk and was on a very nice autobahn...

 

Yeah, I know the 996TT is an AWD and I have test-driven a 997S.
I just cannot put my finger on why this particular 996TT does not grip the road as well as others I have driven.

 

Wheel alignment?

 

I owned a 996TT (had it turned into a 2wd car), and now a 997S. Though both cars had many mods (the 996tt had the whole suspension changed), I still think the 997S handles better, has way more driver feedback, and is more stable at high speeds.