Hi i have a stilo 2.4 abarth, i absolutely love this car but i had to replace the big ends and mains on it..when the motor is at normal temperature it says low oil presure when ideling, oil level is fine..the car smokes when i start it and when accelerating hard..the cars performance is also very poor as it strugles to get all the way to the redline..i also bought a brand new battery, as i heard dead batteries can cause loads of problems...plz any suggestions would be appreciated

Did you check clearances on the oil pump when doing the bearings?
Check compressions. If OK then smoke on start up may be valve guide seals which shouldn't affect performance.

Hi thanx for the feedback..i did get a sollution for the smoking problem, it was the lamda sensor at the cat that was faulty and the performance is also improved..now its still the low oil pressure problem..i had the car in at a engineering shop to replace the bearings so im not sure if they checked the clearances..im not familiar with checking the clearances myself, what tools will i need and what steps should i follow in doing this? do you mabye think i already damaged the new bearings?

Have you checked the oil pressure sensor? Just a thought It might think its low check resistance when engine off run for 10mins then check or if cheap just replace it.

Ill be honest I dont own a stilo id look around the sump bottom end of engine they usually look like the water sensor with maybe 38" or 1/2" nut on and 2 or 3 wire plug on.
For this price on ebay just change it.
300923857246

If you have had enough wear on the bearings the oil pump is probably worn too. To check pump you will need to remove it and check clearances internally with feeler gauges. But to be honest if you are going that far just put a new one on.