I just changed the exhaust header to the one with the catalyst removed and added the Cobra 909 Slip-ons. When I bought it used it had a SE air cleaner set up and stock pipes, so all I can say is that with the catless header and the Cobra slip-ons, it has a very deep and somewhat loud sound now. If I would of put the slip-ons on before with the stock header, I could of given you a better idea of the sound difference. Since I was going to do everything at once, I changed everything at the same time. Sorry I can't give you a better comparison on this. I can tell you it seems to rev up a bit more freely, if that makes sense. I think it was well worth it changing to a header with the catalyst removed. Now to get some good weather to ride this puppy and see how if performs!
Phil

 

We also make an 'Unfiltered' headpipe for the 10-16 as well as the 17-18 FLH. $399 is MSRP. Uses stock shields as well.
Sound wise, it is a pretty big difference between stock and no CAT. Not so much dB wise, but the tone is much bigger/deeper.

 

So it’s deeper in sound but not much louder?Is it an X design or an open chamber were the cat would be?Not many pics of the other side.

 

It is an open chamber/collector.

Sorry for the late response-it was the weekend and although still cold for riding it is warming up here in Cleveland so spent some time getting bikes ready to ride-supposed to see 65+ the next few days (rain-but still beats snow).
Thanks!