Your right, the collector contributes to gain or loss in power, but he has no options for that part or the primaries.

 

what you can upgrade is the j pipe. I heard pro-cats, e-cats or some company like that are in the midst of production of j pipes for the 7th gen, but you can always get it custom made for around 300.

 

J-pipe? Is this what the linked part is called? I thought it was a downpipe, but that may just refer to turbo setups.

 

yea the pic in the link is a j-pipe. well thats what me and some other members on another forum call it. Or the topic starter can always do a true dual set up which cost around 500. There's this other guy that did it as well, but I'm not sure of the gains he had.

 

So the pic from the link is a J-Pipe..? What are those?

 

^ it attaches from the headers to the exhaust pipe

 

I'd expect major low-end losses from a true dual setup unless there is a turbo in the mix in which case, there are still major losses at low-end when the turbo isn't active.

 

So changing out the stock and going to aftermarket exhaust will end up in loss of low end power??? That doesnt make much sense to me...

 

he was talking about the true dual set up i was talking about. But it would be cool to have a true dual exhaust though like the RL

 

I meant the dual setup, but for that matter ..... YES. An aftermarket setup will cost some low-end power to make high-end gains. I think that the cat-back upgrade is worth it if the pipes are sized properly (2.25" for a 4 & 2.25 or 2.5 for a 6). Headers or the down-pipes are worth it on a 6 only IMO.