I have a FXSTC 2007.Are there any slipons available that will improve the sound
withoutout having to do anything else.

 

Rush slip-ons get my vote. Very nice sound. I have a used pair of Rush 2" baffles. w/ bologna cut for sale. $180 ( off my '07 Night Train). They have less than 500 miles on them. I went with V&H Big Radius.

 

SE's, Rinhart's, or try J&P Cycles, they carry a few others also....................

 

Got some HD slash cuts for my 2008 fat boy rated at 80db with bolt on baffels.
Are these any better than stock ,looking for a better harley sound

 

I have the Rush slip ons with 2.0 baffles, everyone comments on the deep sound. Quiet when you need to be and roars when you get on it.

 

Rush slip ons. 2.0 baffles, ....... with the 2.0's, no need to make any fuel adjustments.

You want to do a search on this forum for them. There are loads of threads, general consensus is that everyone is pretty happy with them.

Btw, welcome to the forum.