hooker aerochamber's anyone?

Considering the time of year and your location, I would expect some white smoke from condensation from both cars. Also, residual fuel in the exhaust will burn white too. The smoke seems to dissipate quite quickly which I'm thinking may point to condensation.

I think you just need an to do an "Italian tune up" on the Duster to blow the crap out of the exhaust and loosen the rings up a bit, then see if you still got smoke. A little black smoke isn't necessarilily a bad thing without a load on it. That black smoke will sometimes dissapear on the highway under load. Also, judging by the idle of the 318, I would say you have a decent size cam in the 224 to 228 duration at .050 lift range. The overlap will spit some fuel in the exhaust at idle anyway. Those Jegs mufflers make the 318 sound wicked too, but I'm partial to the Hookers since they sound a bit deeper and a little quieter.

Are you running cast or forged pistons in the 318? Forged will burn a little oil when started as they run looser and need to expand.

Thanks again,

Joe