I know there have been posts on this subject many times, i just got done reading about six pages worth of them. I have an 07 ls with a K&N SRI, and have an lsj downpipe that i haven't installed. Is the stock ss/sc exhaust worth it? I'm told that the pipe goes from 2.5 to 2.0 for the over axle piece. I'm not looking for sound, just a little better flow that the pea-shooter thats on it now.

 

I'm pretty sure the SS cat-back is 2.25", and it does taper down a bit. But, compared to the tiny exhaust piping on the stock LS, it has to be an improvement.

 

i have the whole lsj exhaust on my car and thought it was worth every penny

 

Did you have any trouble with the cat hitting the front sway bar?

 

I have the complete LSJ exhaust also, and no clearance problems with the downpipe.

 

Wonder why others have made comments on fitment, did you feel a difference with the downpipe and exhaust?

 

I first installed the LSJ exhaust manifold and cat-back, and felt a little difference. However, after the downpipe install, I did feel a noticeable increase. I think you need the whole system to get the desired affect.

 

I think that the LS is 1.7" over the axle. 2" > 1.7"

 

Well sounds like i'm going to go with this setup, since everyone wants an arm and a leg for a catback