Originally Posted by Steve30
Well first of all running a narrow tire doesn't help with putting the power down to the ground. You are also putting a lot of stress on the other suspension components due to the extremely low profile and pressure of the tire. Also, if you have high performance suspension, the car will jump over bumps on the road or track (again due to the inflation pressure). I'm sure there are more reasons. The only way I see them as being advantageous is in drifting as Chris mentioned earlier. I'm not hating on the look because I do think it looks killer with the right combination.
Most of what you said there does not only apply to stretched tires.
Anyone running a low profile will have those symptoms, and stretching does not mean you are running a low profile. For instance, my old wheels in my sig were running a 50 profile, which is not low at all.
Also inflation pressure only needs to be 35-40 psi. Alot of cars, especially newer ones run 35 psi stock. So its not that much more, if at all more.
Any low stiff suspension will perform well under the right conditions, it does not have anything to do with tire stretching, but as mentioned above it does have to do with tire profile.
Your right about running a skinny tire, but in all cases even though the tire is too skinny for the rim width, its still often wider then stock, therefore better for performance or atleast equal to what the car is stock.
As chris said its great for stiffening up the sidewall which is great for drifting, but can also be useful for road course, although not as much, generally a stiffer sidewall is good for racing to eliminate slop. I found my e30 with a 195/50 stretched on a 15x9 alot better handling then the stock 195/65r14's.
Stretching is great for street and drift, not that its bad for track, but your better off running a different set of wheels dedicated to track regardless of stretch or not. Running an R compound on the street costs a fair bit of money if you daily a car.