[QUOTE]Originally posted by jguerdat
[B]If it were that good, the tire manufacturers would be doing it, especially on high-end products.

 

Siping is for ice/slush traction. Check out most any all/4- season radials - they have sipes on them. Winter tires have their surfaces almost completely siped. My X-Ones rain tires have extensive sipes on them, and perform admirably in snow/ice. The tread surfaces of my wife's Nokians are composed entirely of zig-zag sipes. No, sipes are not snake oil. I'd expect aftermarket siping would help a bit, but not be as good as manufacturer siping.

The downsides of siping are increased noise on wet roads and tread squirm (depending on sipe design). I agree with others on this: don't ruin your summer tires by siping them. The compound is too hard when cold, and you won't notice the difference in light of the otherwise terrible traction. If you are going to drive a sports car in the winter you have to buy winter tires.

 

Siping is not recommmended for high performance tires. It's for tires that lack sipes in their design. More info....

 

Waste of time and money. Not to mention the danger factor involved with siping high performance tires.