Best Exhaust setup for a 99 Cobra?
 

I want my car to sound mean and a loud at the same time and i want to gain some hp. what is the best exhaust system i can get. right now it has the stock h pipe and mufflers. Even if it involves removing my cats with a new exhaust system i dont care as long as it is best.

Also later on i am going to do the roush side exhaust set up. what is the best for this set up? i will do it next spring so what do u guys think?

You'll see maybe 3 whp from exhaust. Get what you think sounds best. MAC, Bassani, SLP are all popular choices.

He will gain more than that especially since he has the 4 valve heads.
OP- get some longtube headers(ceramic so longevity) then for performance the x pipe is better(stainless steel for longevity) x pipe o/r for better flow and loudness lastly the cat back is your choice although you're doing the side exits so that will be your finale to the exhaust with this on your cobra you will gain a good deal more than 3 rwhp.

Borlas are bad ass on a cobra with that and an O/R pype that 4 valve should pick up some very nice power.

loud and mean
slp loud mouth 1 or 2
with any o/r x-pipe will sound mean.
as for the side pipes, thats up to you. they can be a problem when going over speed bumps and get in the way if you plan on installing sub frame connectors too. i wouldnt do the side pipes.

I think the 4v actually responds very well to exhaust mods.

Pretty much every exhaust setup will be loud with a new midpipe, catted or not. I suggest something like:

Chambered: MAC, MRT Max Thunder, Flowmasters
Straight-thru: Magnapacks, Borla Stingers, SLP Loudmouth 2s, Bassani

One thing though... stay away from LM1's. You're car will sound like an old ass farm truck with straight pipes.