[Ant]

Even if your engine is virtually solid mounted or urethane bushes etc its still a good idea to fabricate a bracket from your sidepipe to a firm square or round rubber mount, on the chassis. The little round mini type accessory exhaust mounts are not strong enough, exhaust shops have bigger squares items or do what I do and find mounts at a breakers yard, I used Jaguar round mounts on my first cobra!

The operative word is "stress" and by fitting a suitably engineered rubber mount will help your pipes last longer!