I went really hard the other night with a Nissan 200sx on my tail. Because he was so close, his headlights were showing up that I was pumping out smoke.

The smoke is so thin as to be not visible in daylight or night time (except when headlights are really close!)

The car is basically unmodded except for a straight through exhaust system. I'm wondering if that's increased flow velocity therefore making the catalytic converter less efficient?

The other thoughts are that the stock ECU runs the mixture slightly rich and timing slightly retarded, so maybe it's the design that the engine smokes a little at WOT, but I've never noticed it (Never having had a car on my tail at WOT - not many cars can keep up!)

 

If it's black, it's due to the engine running rich so it doesn't melt down the piston tops. It's normal. Also, I haven't seen it in this car but both my '94 Prelude VTEC and '97 Prelude SH produced LOTS of black smoke out of the pipe if it had been a couple of days without lots of WOT. It appeared to be soot buildup in the exhaust system that got blown out with a couple of runs through the gears...

 

Headlights "really close"....Nissan 200ZX? Give me a break!! If anything your oil level may be too high.

Utah

 

*lol*

Yes. I know the Stock 200SX is not very quick compared to an S200, but did you know that with a simple chip costing less than $400 they can make their machines go 186Kw? (As compared to S2000 of 176Kw, or a stock 200sx of 142Kw)

The 200SX is severely detuned for the Australian market. The chip advances timing, mixes fuel more agressively and turns up boost. Trust me, there are very few stock 200SX here.

The oil in my car is a little high. They overfilled last service. But in that case, shouldn't it be smoking all the time, not just at WOT?