two jacks are enough to lift up the rear side of my car to install catback
exhaust system??

 

Depends on how big you are. I would say yes, but be careful. Most exhausts come i three pieces that are seperated into a y pipe or h pipe, a straight pipe and then the muffller system itself. You can probably put the y pipe and straight pipe on then jack up the back or vise versa.

 

I hope you are using jack stands rather than "2 seperate jacks". Most exhaust systems come with the y pipe which would probably require you to have the front end in the air. Unless you are toothpick skinny

 

I did mine with only two jackstands, it is possible but you better be skinny and you better be ready to be very uncomfortable and squished. I would definitely recommend 4 if you want the job to be less painful and necessary if you are even really an average sized person.

 

Hopefully you don't have rusted bolts mine was a bitch to take off because of the rust. I used a ratchet with a breaker bar to take them off