Hi
I have a RAM 500 set-up in an Avonds Rafale, full by-pass and double walled pipe . Mine is 10mm from the end of the cone to the front of the pipe. It's a Garry Muller bypass and a tam Pipe. they work well together, turbine is running sweet 520 c tail pipe max temp. contact me off list if you want to talk further or some photos. I am in the UK as well.

Ian R