// The PING))) is triggered by a HIGH pulse of 2 or more microseconds.
// We give a short LOW pulse beforehand to ensure a clean HIGH pulse.
You are changing the time the pulse is high to 5 micro seconds, but acording to the comment above, the pulse should be 2 OR MORE micro seconds, so it probably doesen't have any negative effect.
The question is What was it before you changed it, and why do you want to change it ?