[Roadsters] Smoker?

[Dave Cooke]

My 68 1600 has recently started smoking more than usual out of the tailpipe.
It's always ran with a bit of exhaust smoke, but usually after warm up, it
would only smoke a bit when taking off at an intersection after waiting for
a light.
Now, it's smoking all the time! So, looking for a little help diagnosing
this issue...

Here's what she looks & sounds like today -
http://gallery.me.com/cookefam314/100178/Smoker

She runs fine, carbs are adjusted & plugs look tan, no backfire, plenty of
acceleration.
The smoke does leave a chalky black dry residue, it's not wet or oily, and
it wipes off the tailpipe easily.

Dave Cooke
Lake in the Hills, IL