Yes! (and they will leak, eventually)
I recently installed the JBA titanium ceramic coated shorty's with SRT 3-layer gaskets and SRT bolts (factory dipped ends with heat activated loc-tite), and what a great boost in torque. Direct bolt up to the stock system.
I recommend that you also schlock on a thick bead of orange RTV on each collector where it bolts up to the cats to ensure a nice, leak free installation. I did, and no issues whatsoever with smell, codes, cat contamination, etc.
If you're going that far, look at doing a custom y-pipe to rid yourself of the ridiculously restrictive stock one (a pair of 2.5" pipes smashed into one, and then out to the rest of the system). There is a real net in torque in doing this mod too.
Features & Benefits Mandrel bent stainless steel tube Proprietary JBA Firecone collector Factory style emission connections Extra thick collector domes 3/8" thick machined flanges with Oversized exhaust ports JBA shorty headers are one of the foremost performance upgrades you can bestow upon...
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My $0.02