smoking when hot

so for the past couple of days my 318 has been smoking out the tailpipes when it warms up. when it is cold or just warming up its fine, but as soon as it reaches operating temp it starts to belt out a light greyish smoke and it smells more like gas than anything. the motor is barely over a year old after a complete rebuild. it has hardly any miles on it since i only work about 3 miles from my house and i only drive it about twice a week. i thought maybe the choke was stuck on but it was wide open when it warmed up and i even pulled the airhorn off to see if something was wrong inside but it all looks good. it is coming out of both pipes and i don't have a crossover pipe so it has to be something common to both sides correct? anyone else have any ideas?
Author: admin