My engine has recently started to breath heavy (smoking) from top breather valves, i have no PCV system on them only little K&N filters, would like to know possible reasons for this, have i done a ring?

I could make a few jokes from the language you have chosen, but I won't
You are probably getting oil blow-by from a disintegrated compression ring land.
Do a compression test at least, or a leak down test ideally.
When I did up my daughters SR20DET engine, it had destroyed the top rings and filled the inlet manifold with an oily sludge.
I don't think there is any good news for you Oh, it's PCV, Positive Crankcase Ventilation not PVC

_________________
Regards, Graeme
Just trying to help...
http://nissanman.shutterfly.com/
graemes@internode.on.net

Damn, so sounds like a rebuild is in order......this will be fun

Do the testing first, just for interest sake.

_________________
Regards, Graeme
Just trying to help...
http://nissanman.shutterfly.com/
graemes@internode.on.net

you shouldn't have filters on your breathers anyway. needs to be drawing it out of crank case, if you're not running pcv.

run your lines into a catch can, then one line off this back to your intake pipe (just after air filter)

_________________
1600 with FJ20 & Simmons. something different.