I have had my test pipes for a little over 2 months maybe i dont drive my car daily maybe once to three times a week and rarely. Today i took my car up to japtrix. Since i put the test pipes the car was throwing a little smoke i never seen the car from behind while its driven so i got a little worried ny friends told me that when i downshifted a poof of smoke comes out not a little poof but not either huge poof and then it starts to fade but doenst dissapear. What do you guys think. Do you guys know what this can be.

 

Anyone has had experience or something with this.

 

Sounds pretty typical of a car without cats and I wouldn't worry about it. If something more serious comes up or it gets worse, then have it checked out.