blue smoke (new block and rebuilt heads tho)

[sleeper3000]

91 with 130,000 miles on everything but the block and heads and clutch.

it only smokes when its warmed up and has a steady blue tint smoke coming out. you can really notice it when not moving and just rev it up. have heard it could be the vss but they are rebuilt heads with new vss and lifters and everything. so i'm leaning more toward maybe a turbo problem. the old block and set of heads look fine but just had some carbon build up on them but not to bad. so i dont think the oil is getting in the combustion chamber. so most likely its coming from the turbos. i've checked the intake y-pipe and i can see oil coming from the rear turbo but that could have just been from the pcv sucking oil into the intake cuz of blow-by.

being that its a new block and pretty much new heads thats why i think its the turbo or turbos getting ready to go out. has anyone else had this problem fixed by replacing thier turbos? like i said it only does it when it gets hot and the oil thins out. if i put 20w50 oil in the car it stops the smoking some.

any input into what might be the problem would help alot.
thanks
mark