Hello to all of my people! Help me play a prank on my friend :)

[toyotagf]

Hey everyone!
I'm not sure if I should write it here, but since im a proud owner of a 5th Generation 4 runner, I thought I should talk to my people ^^
As you can see in my last and first post, I'm a big kidder,
I love joking around, and my friends know that..
I actually ordered this exhaust whistle
http://www.twenga.com/price-exhaust-whistle.html
and I was wondering if it worked every on any kind of exhaust pipe?
Is it really annoying?
Are you sure the person wont notice it?
I intend on placing this on a friends car that is going cross country, its is going to HILARIOUS, shes going to kill me! but dont worry I'm going with her, so I'll take it out, after a while! (hopefully she wont see this!)
have