What would happen if the electronic cam controls were diconnected from an M120 engine

1) Idel rough.
2) Would it just have reduced power and poor fuel economy.
3) Would all the valves hit the pistons and cause disater.
4) Would it not even start.
5) Anything else you can think of ??

I will be installing an aftermarket engine managment system (Megasquirt) onto a 1996 SL600. For the moment camshaft control will be a challange. I only need this to be driven for preliminary testing.

John Roncallo