1985 Mercedes Benz 190e Camshaft bearing cap torque

I have a snapped exhaust camshaft in my 1985 Mercedes Cosworth 2.3. I have bought a camshaft on ebay but am unsure what the torque value should be for the bearing caps when fitting the new camshaft. I am keen to get it right as the old cam seems to have snapped when the bearing cap came loose!