1992 Other Vauxhall Models blowing alot off smoke from exhau

hi,i got a calibra 2.0 turbo,i havent started it for about a week,and when i recently started it and took it for a spin there was alot of smoke from the exhaust when it was stood at lights or a junction and when its iddling on the drive.i aint loosing no water or not overheating either,so i dont think its the headgasket as i had that done 6 months ago.i go a dtm exhaust on it,and i was wandering if alot of water had got in the exhaust.thanks charlie