I was running to 140 mph, just for the fun of it , by the time it reached around 95+ the car felt unstable, not horrible shaking just enought to make u think, but i got to 140 anyways, do ur cars do this?, i have new tires 300 + miles in it and i have a stock suspension and wheels, i also just had an alignment, what do u think I should do?

 

if your alignment is correct, then your wheel weights are wrong, which means your alignment is wrong. If you wheel weights are right, then your wheel(s) are bent, cracked, etc......

Or could be something more expensive like control arms.....just thingking out loud here....

 

I've been up around there and the car feels great a high speeds. The only negative i have is that it feels a bit too light for high speeds.

 

maybe im wrong in describing it, its not vibration maybe, too bouncy is the term.

 

nah it should feel smooth. Maybe the road?

 

yeah i felt that same thing at high speeds.car doesn't feel stable after about 95 or so. i think it is maybe because it's too light

 

Try a lower front X brace. It made a difference in stability for me, especially for rough road surfaces.

 

The S2k has a shorter wheelbase then other cars, which at high speeds will be less stable aerodynamically then other cars that have a longer wheelbase.

 

This car makes a ton of lift at the rear at 140. Not enough to be a huge problem on a straight, flat road, but definitely noticeable.

 

What tires are you running? My car felt very unstable with my Toyo Proxy4s (only 225 in the rear) and It feels a lot more "attached" or solid with my Nitto 555s.