Ok. Went for a cruise in my 85 SS the other day. I drive it easy. Don’t want to break anything. For some reason it started smoking blue smoke from both tailpipes. It has true duel exhaust so it’s from both banks of cylinders. Parked it. Went for an extended cruise tonight to see if I could duplicate what had happened previously. Nope. Runs perfect . No smoking whatsoever. Any thoughts would be greatly appreciated.

 

Blue Smoke is usually a sign of a Oil leak into the cylinders sometimes happens when the oil that is in the Heads bypasses the valve and gets into the cylinder. Could be that the seal on the top of the valve at the rocker is weak.
This could happen on both sides as well. I have seen Mechanics take the valve cover off and run the engine to see which one is the issue. But I wouldn't do anymore.
Might just need some good Lucas oil additive to help those seals. Try that on the next oil change.

 

Thanks for the info. Greatly appreciated!

 

It could also be the PCV valve.
Remove each spark plug then examine for fouling to see if it's across the board.

 

Check not only the pcv but the breather side of the pcv. Too much vacuum inside the motor and it will pull oil pass the weak valve seals. ( It's a 1985 so the seals are going to be weak).