What could be the probable causes of this? I don't have any funny noises, oil doesn't look like milkshake, I don't appear to be losing coolant.

Bad valve seals?

 

how much white smoke is it? the lt1 has something built in from the factory to allow a little blow by to lube the lower end or something like that. from what i hear, its normal and its suppose to do it.

 

I have the same problem in my 87 Iroc w/ 350 it blows whitish blue smoke out the tail pipes for about 5 secs. then goes away enough to gage me when I back in to it right away.
I am just chalking it up to the engine needs to be re sealed which will be done this winter.

 

Yup, bad valve seals. Speaking of which, I have to replace those on my car soon, it's getting worse everyday.

 

If you use positive type seals on both the intake and exhaust (instead of positive on one and umbrella on the other) they won't start leaking again so quickly. The umbrella seals tend to harden and break over time, the positive's aren't as bad about it.

 

Fig as much with my car it has a 133k miles on it most of the parts are Factory org.

 

Don't you need to machine the guides to take positive seals, or am I mistaken on that?

 

Not to my knowledge. You put them on just like the umbrella seals, but they have a little spring ring around the top and bottom that holds them tight against the valve stem and guide boss.