Ok the chart didn't show up correctly. But here it is again:
It tests the effects of tuning the timing and mixture on emissions.
Standard | Timing retarded 10 degrees | Timing advanced 10
degrees | Mixture richened | Mixture leaned
>HC 1 0.78
1.14 1.39 0.88
>CO 14.45 11.59 12.96
81.04 9.79
>NO 2.91 1.89
5.18 0.71 3.03
>O2 22.29 19.77
23.76 17.4 25.36
>CO2 305 307 298
246 310
>
> _________________________________
>
> Steve
> 70'1600
>
>
> ----- Original Message -----
> From: "John F Sandhoff" <sandhoff@csus.edu>
> To: <datsun-roadsters@autox.team.net>
> Sent: Monday, May 23, 2005 10:59 AM
> Subject: emissions and ignition timing?
>
>
> > Any smog gurus out there? Please, no guessing on the following.
> > I need to know what really happens :-)
> >
> > What is the effect on unburned hydrocarbon emissions (HC)
> > if the timing is retarded?
> >
> > Later (68+) cars were set a 0 degrees, making for poor performance
> > but cleaner emissions. I had thought this dropped NOx, but some
> > reading I was doing this weekend implies that retarding the timing will
> > drop HC.
> >
> > So what happens at the smog machine if I back off from 16 degrees
> > to say 4 degrees? Does the tailpipe clean up for the test?
> >
> > (for the astute: No, CA is not back to testing our cars)
> >
> > -- John
> > John F Sandhoff sandhoff@csus.edu Sacramento, CA
|