header wrap on stock exhaust manifolds?
whats the "goal" or "goals" of wrapping the manifolds that you wish to achieve? do you just want it quieter? is it too hot in the car from the engine? are you looking for more power? is your car running hotter than it should be?
if you want it quieter and cooler inside the car just get some sound deadening heat material stuff. personally ive never used it because i like noise but i heard it works well. header wrap probably wont cut noise down at all.
If your looking for more power this is not a very good way to do it. its a big waste of time and money as has been discussed above. it might gain you a very very small percentage of power but will eventual fall off.
if your cars running hotter than it should be this is a band aid for the problem. something is not right if its running hotter than it should be and should be fixed properly.
im not trying to sound like a jerk. i just would like to talk you out of buying header wrap as it is not practical.