Austarion

I recently bought some new engine mounts and I was about to instal them, however I found that there's a metal surround for the rubber/poly mount.

On one side (passenger) this surround slips straight off and can be used with the new engine mount. On the other side, it's welded (looks factory done) to it and can't be separated.

I assume the surround is there to ensure the rubber can't be over-stretched, yeah?

Generally the metal surround is to prevemt the motor moving forward and ventilating the radiator under heavy brakeing especially if the mount is stuffed

Yeah, I figured it would be something along those lines. Surely your gearbox would have to come free from its mountings to allow that to happen, but hey, stranger things have happened!

I'm considering not using them as it's a track car and everything gets inspected after each meeting, so it would be unlikely for the mounts to get so worn as to allow such movement.

They act as stiffeners. On a track car especially I'd recommend them be retained.
Driver's side is unboltable as you say, but the passenger side is not. Either try and separate the weld, or use a 2nd driver's side shroud on the passenger side.
Driver's side mount has added advantage of mounting the heat shield to protect the rubber mount from turbo & dump heat.

Dont really need it on the drivers side, more the passengers side. Its there so if the mount breaks the engine will still be retained, and its only the passengers side that will tear with the torque reaction.

so digging up an old thread.

My motor is currently supported by an engine crane because i've pulled out the passenger's side mount only to realise that I can't get the bracket off.

How the fuck are you supposed to replace the mount then?? This is infuriating.