[alfa] CA emissions test, high NOx, test numbers, etc.

["John D. Fox" <jdfox@xxxxxxxxxxxxxxxxx>]

One detail that isn't in the discussion so far - was this an unloaded (
idle and 2500 RPM test) or a loaded test on a dyno? If on the dyno, what
engine rpm and road speed was it run at ( or what gear was it tested in
at what road speed)?

This is significant, in that the NOx is basically produced by high
combustion temperatures. If the test is done by running the car at 20 MPH
in 5th gear - I'd expect much higher NOx than running at 20 MPH in 2nd
gear - the issue is that lugging the engine at the low RPM at a relatively
large throttle opening would have higher peak combustion temperatures.

It is still true that the other numbers ( CO, CO2, HC, O2) are important,
and that unless the O2 sensor is working, ignition advance on the motronic
is working, etc. then you need to fix all these things first.

I have asked several times, and tried to find out the test procedure
recommendations for engine RPM while doing the dyno test. I've never had a
consistent answer. As an interesting note, the owners manual for my 1972
SPICA injected Spider has instructions never to lug the engine or drive it
under high load below 2000 RPM - it basically suggests always running
above 2000 RPM. Maybe Don Black will comment if that was there so that
testers would run the engines above 2000 RPM in the federal test
cycles?

                                                          John
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