Hey floortom here... i lost a head gasket and replaced it. after starting...got this huge plume of smoke. checked plugs, ect, started to dougt my work... tourque wrench...ect then i took off the y pipe to see which side was smokin...after start.. no smoke from motor...reconnect the pipe and it was like a tire fire. ran it in 3rd for 10. mi. @30 mph.down a rual road and it cleared out.. any imput?

Yep, left-overs in the exhaust. Happened to me the first one i did. The longer it ran the better it got.

I too have had this happen. Probably due to the orientation of the exhaust - everything wants to flow toward the lowest point with a Subaru engine. I try to stick rags in the y-pipe before I pull the heads or just remove the pipe completely - helps stop fluids (and sockets, tools, etc ) running in there as you dissasemble.

 

GD