smoking vti

:screwy: i am the owner of a 97 civic vti 5dr,and have been for around 15 months.the car has part dealer history e.g oil changes.since owning the car i have done three oil changes with castrol magnatec but the car seems to be using oil from time to time.i am getting blue smoke but seems to be on higher revs and in vtec range,at low revs the car seems ok.the car has a powertec cone filter and cold air feed plus a full stainless mongoose exhaust with de-cat pipe.valves have been adjusted and have been informed that the car has unburnt fuel but my fuel economy seems ok.the car has covered 90,000 miles.could the smoke be down to a piston ring or maybe valve stem seals.please,please hit me back with some suggestions,appreciate it thanks, titch

Have a friend start the car after it's been sitting over night and look for a puff of blue smoke on start-up. If yes, it's probably valve seals. If not, rings. Do a compression test also to try and pinpoint the trouble cylinder.

A compression test will tell you.
If your compression is good, it's probably the valve seals which can be
replaced without removing the head.
If the compression is low you'll have to ddetermine if it's from valves or rings.
With rings, squirt some oil in the cylinder and check again, if it is better
it's the rings. With rings the compression gage will usually pump up in
stages before peaking. With valves it'll go to it's peak right a way.