Timing versus smoke (coal)

[whiteboyslo]

Did some searching but all I got were threads with people wanting to 'roll coal'

What relationship, if any, is there between the timing of an engine and the amount of black smoke it emits? My truck has always smoked a bit when I lug it heavily (close to WOT but at a low enough RPM to not build boost), or at the top end near the governor if working it, or with a healthy jab of the go pedal while not under load (neutral). Just wondering if getting the timing back in the right ballpark (was about 4° BTDC, now 8-8.5°) is going to HELP or hurt this. I've only put a few miles on the truck since I set the timing, but I could swear it's much easier to get it to smoke than it used to be, and that there's a bit more than I'm used to. But then again, I've been known to be pretty myself (well, paranoid to say the least)

Mike

 

[Oog]

Hot weather less air. My truck doesnt smoke in winter sure to denser air

 

[Black dawg]

more timing = more black smoke.

 

[Kevin 007]

If its on the retarded side, it will smoke blue and if its really far retarded, it will be whiteish blue. X2 on the above, the further you advance, the more black smoke is emitted. You are timed just right in my opinion...

 

[IDIDieselJohn]

I noticed my van on cold mornings, always shoots abit of constant black smoke when accelerating normally when the timing advance is still on, as soon as it kicks off, smoke goes away with no change in accel speed.

At that point, only smokes black under full throttle, at any RPM.