So I discovered the middle silencer box on my exhaust has a hole and is blowing out the side.

NOW..... We all love the sound of a V8 grumble. So do I buy and new exhaust OR do I cut out middle section have a straight through to rear box and enjoy the sounds of other people's windows smashing as I throttle my 4litre V8 injection.

If I go for the straight through will it fail an MOT on emissions or some other rubbish???

Boxes are only there to make it quieter so wont affect the emissions. I run my 300tdi with just a back box and its fine.

Go for it.

In the mot testers manual any interference with a vehicles exhaust to make it louder is a reason for rejection, u could can do search for the official wording.

Whether you engines ECU can adjust for the lack of back pressure with the centre box missing I don't know, if it can't u will have issues. Why not fit a stainless steel Cat Back system and forget exhaust problems in the future.

I fitted a Janspeed system seven years ago, straight away the idle speed went up to 2000rpm but settled down to normal after a couple of minutes when the ECU decided to do something, the engine is certainly more responsive so very happy with my purchase.

I did this to my 3.9 RRC

https://www.youtube.com/watch?v=FAsw1whnc8Y

Was very boomy at about 2000RPM and not actually pleasant in the cab all that much. Go for a muffler in the middle and delete the backbox.

Fine for MOT.