Have problem, need your help!

[y b a stuntman]

Had my 87 Gn out on the freeway and stepped on it really good. I got a big puff of smoke and it smoked a little more till I got the car home. There is a loss of power it does seem like the turbo is working and I have a little bit of a oil leak. When I start the car after a little bit of time smoke is coming off of the valve cover area oppisite of the side the turbo is on. Please Help with your thoughts.