decat pipes for a 300zx

[lord-doof]

hi,just bought an rs r decat exhaust with kakimoto racing back boxes???? was going to fit today but then wondered what i do with the origional little extra pipe from the cat? i am starting to think maybe its not quite a straight swap is it??? bought 2nd hand because mine snapped(sounds so much sweeter since it did tho),any advice about whats requiret would be sweetly appreciated
cheers,,,, doof.

 

[SRRAE]

Its been a while since I was in the know on these cars, but I think it was to do with the AVI Valves. They blow unburnt fuel from the engine straight on to the cats to help them warm up. Cats only work once up to temperature which I think is several hundreds of ºC maybe even 1000+.
Since most AVI valves no longer work (The old gurgling problem) they are not really needed.