jetwings, in all honesty, I think it would be very unfair of anyone here to raise any serious expectations that you might secure a comp upgrade without relatively high Skywards status ....ie Gold or above, as mentioned by lighthand.
The fact is, op-ups these days are not given on some sort of request basis, but are invariably pre-determined by flight control within defined criteria.
If you're really keen to get a bigger seat, then the reality is you will need to stump up cash or miles.
(no doubt someone will now pop up to say that they were upgraded on their very first flight with EK, in the same way that people win the lottery .....
)