Just ordered one of these after deciding I love my loud exhaust but just not all the time, and want to not p1ss the neighbours off too much.

http://www.prostreetonline.com/news/apexi_decs_ecv/

It'll be a bit of work to fit I suppose as I'll have to remove the centre pipe & get someone to weld this in or something but if it does what it's meant to it'll be the business. Nice and quiet around town then it'll open up when I put my foot down.

What's people's theories on something like this & how well it'll work?
It gets installed I believe just after the downpipe and will restrict gas flow by a variable amount through the system. Is this likely to make much of a noise difference on a full decat, straight through system?

The other thing is back pressure. I may be mistaken but I always had the impression that turbo engines don't like back pressure but NA ones do?
If that's correct it might equate to better response lower down the rev range before it opens up more maybe, or is that wishful thinking?

Be interested to know what people think....