What in the....

Not one single person mentioned Spin Tech?? "If it sounds too good to be true, it must be Spin Tech. Go to their website.
I'm running shorties into 3 inchs into dual spin tech mufflers (not true dual exhaust)

 

im running the cat back for a 4th gen ls1 engine. my header/y-pipe combo is similar to that of the 4th gen. its a dynomax that matches the setup of an slp loudmouth, however the y-pipe design in the rear sends 90% of the exhaust out the driver's side. mounting was almost a direct fit although the tips dont come out evenly. i plan on swapping the tips anyway as well as cutting a slit into the y and adding a plate to divert more out the passenger side. its sounds like nothing else. clips avail on youtube, look up rcravincase or darlingreject

 

http://i252.photobucket.com/albums/h...0247ae15e0.jpg

http://i252.photobucket.com/albums/h...129_123334.jpg

Here's my set up, I'll take some clearance pics. Its well tucked. Has cats high flow cats and spiral mufflers. Clearance is no issue even with speed bumps
It does go under axles not over. And yes this is a true dual 3" with h-pipe.

Cats are flanged about 4 inches from my long tubes and those are pace setters.

 

Yes I know mines a 4th Gen but I had a duel setup identical to this on my 85, all the catbacks from 82-02 are the same with a little modification.