One of the engine mounts has failed. It just need bolting back to the font of the engine as this is not a weight supporting mount it just stops the enige from twisting under torque.
If it 'just needs bolting back to the front of the engine' why hasn't it been done? I fail to believe that any 'bolting' is going to rectify this problem.
The other mounts are just a poor design and could do with redesigning them but that the only major thing letting this awsome car down.
So one mount has already failed and it also doesn't sound like the remaining mounts are up to the job. Doesn't really fill you with confidence does it.
Also the way the brakes are plumbed from the master cylinder need changing as they had been plumded in single circuit so they are not as power full as the they could be and its a dangours method to plumb breaks. I did not know they were done like this and only found it out at a later date, but its not a hard fix but i wont let the car be driven away with it like that so i would perfer it to be trailored away.
Not only is there a possibility that the engine might fall out, there's also the possibility that you might not even be able to stop the car to retrieve it. On the plus side, I suppose having the gearbox and sump dragging along the road might provide the brakes with a little assistance.
the car started smoking from the breather pipe so i think the head gasket could be on its way out. The car had never over heated but i stop driving it when i noticed this
Sounds more like a damaged piston or two. Not to worry though, that can be fixed before refitting the engine that's just fallen out.
The turbo on the car is a ct20b, the uk celica spec turbo with the stonger steel shaft, the car did blow a very small amont of blue smoke under full boost so i think the seals could need refurbishing.
This could be a plus point. If the engine is fucked, the turbo might actually be OK!
IMO for a car that potentially has a fucked engine that's about to fall out and a braking system that on the face of it isn't up to the job, asking 4 grand is being extremely optimistic. The car may have already had an expensive engine conversion carried out, but the conversion sounds like a complete failure. It's going to take a lot of work to get this car to a reliable state where the owner can safely enjoy it and the work required in getting there isn't going to be a free and simple bit of tinkering on the driveway at home. Fare play to the person that takes this thing on, but if the £4,000 asking price is paid I'd say they've just been mugged.