Exhaust straps

Just started to fit a stainless system (XPower) onto the tf115.
Bought (well nearly) off fleabag along with various other bits that included a sports cat. But it hasn't got a strap and shows no indication of ever having been "strapped". As it a different size to a standard box a bit of modification will be needed. Is one required and what does it actually do?

It gives the silencer extra support.

The smaller back boxes don't need the strap. I've the MGOC Supersports fitted and it comes without a strap as the MGOC say that it's not needed. And extensive miles since it was fitted confirm that it is OK 'strapless'.

Richard

It seems to rotate the box and hold it so that the exhaust pipes poke out at he right angle. the is a bracket on the strap that bolts onto the Cat flange. You can get one for about thirty pounds from Rimmers.

Ive just dismantled my exhaust system.....the back box was not held on by a strap.....the top half was still there bolted to the cat.....the bottom half was missing with a mark around the back box to show it was once there......my tail pipes were sitting to high and it was starting to get on my nerves when i looked at them.......but the price of a new one....crikey.......is it just me or are those pricey......heres a picture of my car i can tell from it there sitting a bit high..........when i see a good one at the right price ill put one on.....i only need the bottom half.....

I suspect that a MoT man would probably fail the car if only half the strap is there. They seem to delight in telling me that my pug207 has a severely corroded strap!!
I can see that a smaller box doesn't need a strap so the answer is not to take two cars to the same test station on the same day
If they have different exhausts.
As far as I can see the strap doesn't actually support the box but does attempt to prevent flexing and then failure of the Cat, pipe or box???

well my tf just failed its test on a minor leak from the exhaust front pipe....nothing was said on any of the mots about half a strap.....to be honest you cant really see much of the top half.....and the rubber mounts hold it well.....but ive heard the odd knock now and again as the tail pipes must hit the bumper